MONIT(1)                         User Commands                        MONIT(1)



NAME
       monit - utility for monitoring services on a Unix system

SYNOPSIS
       monit [options] {arguments}

DESCRIPTION
       monit is a utility for managing and monitoring processes, files,
       directories and devices on a Unix system. Monit conducts automatic
       maintenance and repair and can execute meaningful causal actions in
       error situations. E.g. monit can start a process if it does not run,
       restart a process if it does not respond and stop a process if it uses
       too much resources. You may use monit to monitor files, directories and
       devices for changes, such as timestamps changes, checksum changes or
       size changes.

       Monit is controlled via an easy to configure control file based on a
       free-format, token-oriented syntax. Monit logs to syslog or to its own
       log file and notifies you about error conditions via customizable alert
       messages. Monit can perform various TCP/IP network checks, protocol
       checks and can utilize SSL for such checks. Monit provides a http(s)
       interface and you may use a browser to access the monit program.

GENERAL OPERATION
       The behavior of monit is controlled by command-line options and a run
       control file, ~/.monitrc, the syntax of which we describe in a later
       section. Command-line options override .monitrc declarations.

       The following options are recognized by monit. However, it is
       recommended that you set options (when applicable) directly in the
       .monitrc control file.

       General Options and Arguments

       -c file
          Use this control file

       -d n
          Run as a daemon once per n seconds

       -g
          Set group name for start, stop, restart and status

       -l logfile
          Print log information to this file

       -p pidfile
          Use this lock file in daemon mode

       -s statefile
          Write state information to this file

       -I
          Do not run in background (needed for run from init)

       -t
          Run syntax check for the control file

       -v
          Verbose mode, work noisy (diagnostic output)

       -H [filename]
          Print MD5 and SHA1 hashes of the file or of stdin if the
          filename is omitted; monit will exit afterwards

       -V
          Print version number and patch level

       -h
          Print a help text

       In addition to the options above, monit can be started with one of the
       following action arguments; monit will then execute the action and exit
       without transforming itself to a daemon.

       start all
          Start all services listed in the control file and
          enable monitoring for them. If the group option is
          set, only start and enable monitoring of services in
          the named group.

       start name
          Start the named service and enable monitoring for
          it. The name is a service entry name from the
          monitrc file.

       stop all
          Stop all services listed in the control file and
          disable their monitoring. If the group option is
          set, only stop and disable monitoring of the services
          in the named group.

       stop name
          Stop the named service and disable its monitoring.
          The name is a service entry name from the monitrc
          file.

       restart all
          Stop and start all services. If the group option
          is set, only restart the services in the named group.

       restart name
          Restart the named service. The name is a service entry
          name from the monitrc file.

       monitor all
          Enable monitoring of all services listed in the
          control file. If the group option is set, only start
          monitoring of services in the named group.

       monitor name
          Enable monitoring of the named service.  The name is
          a service entry name from the monitrc file. Monit will
          also enable monitoring of all services this service
          depends on.

       unmonitor all
          Disable monitoring of all services listed in the
          control file. If the group option is set, only disable
          monitoring of services in the named group.

       unmonitor name
          Disable monitoring of the named service. The name is
          a service entry name from the monitrc file. Monit
          will also disable monitoring of all services that
          depends on this service.

       status
           Print full status information for each service.

       summary
           Print short status information for each service.

       reload
           Reinitialize a running monit daemon, the daemon will
           reread its configuration, close and reopen log files.

       quit
           Kill a monit daemon process

       validate
          Check all services listed in the control file. This
          action is also the default behavior when monit runs
          in daemon mode.

WHAT TO MONITOR
       You may use monit to monitor daemon processes or similar programs
       running on localhost. Monit is particular useful for monitoring daemon
       processes, such as those started at system boot time from /etc/init.d/.
       For instance sendmail, sshd, apache and mysql. In difference to many
       monitoring systems, monit can act if an error situation should occur,
       e.g.; if sendmail is not running, monit can start sendmail or if apache
       is using too much system resources (e.g. if a DoS attack is in
       progress) monit can stop or restart apache and send you an alert
       message. Monit does also monitor process characteristics, such as; if a
       process has become a zombie and how much memory or cpu cycles a process
       is using.

       You may also use monit to monitor files, directories and devices on
       localhost. Monit can monitor these items for changes, such as
       timestamps changes, checksum changes or size changes. This is also
       useful for security reasons - you can monitor the md5 checksum of files
       that should not change.

       You may even use monit to monitor remote hosts. First and foremost
       monit is a utility for monitoring and mending services on localhost,
       but if a service depends on a remote service, e.g. a database server or
       an application server, it might by useful to be able to test a remote
       host as well.

       You may monitor the general system-wide resources such as cpu usage,
       memory and load average.

HOW TO MONITOR
       monit is configured and controlled via a control file called monitrc.
       The default location for this file is ~/.monitrc. If this file does not
       exist, monit will try /etc/monitrc, then @sysconfdir@/monitrc and
       finally ./monitrc.

       A monit control file consists of a series of service entries and global
       option statements in a free-format, token-oriented syntax.  Comments
       begin with a # and extend through the end of the line.  There are three
       kinds of tokens in the control file: grammar keywords, numbers and
       strings.

       On a semantic level, the control file consists of three types of
       statements:

       1. Global set-statements
           A global set-statement starts with the keyword set and the item to
           configure.

       2. Global include-statement
           The include statement consists of the keyword include and a glob
           string.

       3. One or more service entry statements.
           A service entry starts with the keyword check followed by the
           service type.

       This is the hello galaxy version of a monit control file:

        #
        # monit control file
        #

        set daemon 120 # Poll at 2-minute intervals
        set logfile syslog facility log_daemon
        set alert foo@bar.baz
        set httpd port 2812 and use address localhost
            allow localhost   # Allow localhost to connect
            allow admin:monit # Allow Basic Auth

        check system myhost.mydomain.tld
           if loadavg (1min) > 4 then alert
           if loadavg (5min) > 2 then alert
           if memory usage > 75% then alert
           if cpu usage (user) > 70% then alert
           if cpu usage (system) > 30% then alert
           if cpu usage (wait) > 20% then alert

        check process apache
           with pidfile "/usr/local/apache/logs/httpd.pid"
           start program = "/etc/init.d/httpd start"
           stop program = "/etc/init.d/httpd stop"
           if 2 restarts within 3 cycles then timeout
           if totalmem > 100 Mb then alert
           if children > 255 for 5 cycles then stop
           if cpu usage > 95% for 3 cycles then restart
           if failed port 80 protocol http then restart
           group server
           depends on httpd.conf, httpd.bin

        check file httpd.conf
            with path /usr/local/apache/conf/httpd.conf
            # Reload apache if the httpd.conf file was changed
            if changed checksum
               then exec "/usr/local/apache/bin/apachectl graceful"

        check file httpd.bin
            with path /usr/local/apache/bin/httpd
            # Run /watch/dog in the case that the binary was changed
            # and alert in the case that the checksum value recovered
            # later
            if failed checksum then exec "/watch/dog"
               else if recovered then alert

        include /etc/monit/mysql.monitrc
        include /etc/monit/mail/*.monitrc

       This example illustrate a service entry for monitoring the apache web
       server process as well as related files. The meaning of the various
       statements will be explained in the following sections.

LOGGING
       monit will log status and error messages to a log file. Use the set
       logfile statement in the monitrc control file. To setup monit to log to
       its own logfile, use e.g. set logfile /var/log/monit.log. If syslog is
       given as a value for the -l command-line switch (or the keyword set
       logfile syslog is found in the control file) monit will use the syslog
       system daemon to log messages. The priority is assigned to each message
       based on the context. To turn off logging, simply do not set the
       logfile in the control file (and of course, do not use the -l switch)

DAEMON MODE
       The -d interval command-line switch runs monit in daemon mode. You must
       specify a numeric argument which is a polling interval in seconds.

       In daemon mode, monit detaches from the console, puts itself in the
       background and runs continuously, monitoring each specified service and
       then goes to sleep for the given poll interval.

              Simply invoking

                     monit -d 300

       will poll all services described in your ~/.monitrc file every 5
       minutes.

       It is strongly recommended to set the poll interval in your ~/.monitrc
       file instead, by using set daemon n, where n is an integer number of
       seconds. If you do this, monit will always start in daemon mode (as
       long as no action arguments are given).

       Monit makes a per-instance lock-file in daemon mode. If you need more
       monit instances, you will need more configuration files, each pointing
       to its own lock-file.

       Calling monit with a monit daemon running in the background sends a
       wake-up signal to the daemon, forcing it to check services immediately.

       The quit argument will kill a running daemon process instead of waking
       it up.

INIT SUPPORT
       Monit can run and be controlled from init. If monit should crash, init
       will re-spawn a new monit process. Using init to start monit is
       probably the best way to run monit if you want to be certain that you
       always have a running monit daemon on your system. (It's obvious, but
       never the less worth to stress; Make sure that the control file does
       not have any syntax errors before you start monit from init. Also, make
       sure that if you run monit from init, that you do not start monit from
       a startup scripts as well).

       To setup monit to run from init, you can either use the 'set init'
       statement in monit's control file or use the -I option from the command
       line and here is what you must add to /etc/inittab:

         # Run monit in standard run-levels
         mo:2345:respawn:/usr/local/bin/monit -Ic /etc/monitrc

       After you have modified init's configuration file, you can run the
       following command to re-examine /etc/inittab and start monit:

         telinit q

       For systems without telinit:

         kill -1 1

       If monit is used to monitor services that are also started at boot time
       (e.g. services started via SYSV init rc scripts or via inittab) then,
       in some cases, a race condition could occur. That is; if a service is
       slow to start, monit can assume that the service is not running and
       possibly try to start it and raise an alert, while, in fact the service
       is already about to start or already in its startup sequence. Please
       see the FAQ for solutions to this problem.

INCLUDE FILES
       The monit control file, monitrc, can include additional configuration
       files. This feature helps to maintain a certain structure or to place
       repeating settings into one file. Include statements can be placed at
       virtually any spot. The syntax is the following:

         INCLUDE globstring

       The globstring is any kind of string as defined in glob(7).  Thus, you
       can refer to a single file or you can load several files at once.  In
       case you want to use whitespace in your string the globstring need to
       be embedded into quotes (') or double quotes ("). For example,

        INCLUDE "/etc/monit/monit configuration files/printer.*.monitrc"

       loads any file matching the single globstring.  If the globstring
       matches a directory instead of a file, it is silently ignored.

       INCLUDE statements in included files are parsed as in the main control
       file.

       If the globstring matches several results, the files are included in a
       non sorted manner.  If you need to rely on a certain order, you might
       need to use single include statements.

GROUP SUPPORT
       Service entries in the control file, monitrc, can be grouped together
       by the group statement. The syntax is simply (keyword in capital):

         GROUP groupname

       With this statement it is possible to group similar service entries
       together and manage them as a whole. Monit provides functions to start,
       stop and restart a group of services, like so:

       To start a group of services from the console:

         monit -g <groupname> start

       To stop a group of services:

         monit -g <groupname> stop

       To restart a group of services:

         monit -g <groupname> restart

MONITORING MODE
       Monit supports three monitoring modes per service: active, passive and
       manual. See also the example section below for usage of the mode
       statement.

       In active mode, monit will monitor a service and in case of problems
       monit will act and raise alerts, start, stop or restart the service.
       Active mode is the default mode.

       In passive mode, monit will passively monitor a service and
       specifically not try to fix a problem, but it will still raise alerts
       in case of a problem.

       For use in clustered environments there is also a manual mode. In this
       mode, monit will enter active mode only if a service was brought under
       monit's control, for example by executing the following command in the
       console:

         monit start sybase
         (monit will call sybase's start method and enable monitoring)

       If a service was not started by monit or was stopped or disabled for
       example by:

         monit stop sybase
         (monit will call sybase's stop method and disable monitoring)

       monit will not monitor the service. This allows for having services
       configured in monitrc and start it with monit only if it should run.
       This feature can be used to build a simple failsafe cluster. To see
       how, read more about how to setup a cluster with monit using the
       heartbeat system in the examples sections below.

ALERT MESSAGES
       Monit will raise an email alert in the following situations:

        o A service timed out
        o A service does not exist
        o A service related data access problem
        o A service related program execution problem
        o A service is of invalid object type
        o A icmp problem
        o A port connection problem
        o A resource statement match
        o A file checksum problem
        o A file size problem
        o A file/directory timestamp problem
        o A file/directory/device permission problem
        o A file/directory/device uid problem
        o A file/directory/device gid problem

       Monit will send an alert each time a monitored object changed.  This
       involves:

        o Monit started, stopped or reloaded
        o A file checksum changed
        o A file size changed
        o A file content match
        o A file/directory timestamp changed

       You use the alert statement to notify monit that you want alert
       messages sent to an email address. If you do not specify an alert
       statement, monit will not send alert messages.

       There are two forms of alert statement:

        o Global - common for all services
        o Local  - per service

       In both cases you can use more than one alert statement. In other
       words, you can send many different emails to many different addresses.
       (in case you now got a new business idea: monit is not really suitable
       for sending spam).

       Recipients in the global and in the local lists are alerted when a
       service failed, recovered or changed. If the same email address is in
       the global and in the local list, monit will send only one alert. Local
       (per service) defined alert email addresses override global addresses
       in case of a conflict. Finally, you may choose to only use a global
       alert list (recommended), a local per service list or both.

       It is also possible to disable the global alerts localy for particular
       service(s) and recipients.

       Setting a global alert statement

       If a change occurred on a monitored services, monit will send an alert
       to all recipients in the global list who have registered interest for
       the event type. Here is the syntax for the global alert statement:

       SET ALERT mail-address [ [NOT] {events}] [MAIL-FORMAT {mail-format}]
       [REMINDER number]

       Simply using the following in the global section of monitrc:

        set alert foo@bar

       will send a default email to the address foo@bar whenever an event
       occurred on any service. Such an event may be that a service timed out,
       a service was doesn't exist or a service does exist (on recovery) and
       so on. If you want to send alert messages to more email addresses, add
       a set alert 'email' statement for each address.

       For explanations of the events, MAIL-FORMAT and REMINDER keywords
       above, please see below.

       When you want to enable global alert recipient which will receive all
       event alerts except some type, you can also use the NOT negation option
       ahead of events list which allows you to set the recipient for "all but
       specified events" (see bellow for more details).

       Setting a local alert statement

       Each service can also have its own recipient list.

       ALERT mail-address [ [NOT] {events}] [MAIL-FORMAT {mail-format}]
       [REMINDER number]

       or

       NOALERT mail-address

       If you only want an alert message sent for certain events for certain
       service(s), for example only for timeout events or only if a service
       died, then postfix the alert-statement with a filter block:

        check process myproc with pidfile /var/run/my.pid
          alert foo@bar only on { timeout, nonexist }
          ...

       (only and on are noise keywords, ignored by monit. As a side note;
       Noise keywords are used in the control file grammar to make an entry
       resemble English and thus make it easier to read (or, so goes the
       philosophy). The full set of available noise keywords are listed below
       in the Control File section).

       You can also set the alert to send all events except specified using
       the list negation - the word not ahead of the event list. For example
       when you want to receive alerts for all events except the monit
       instance related, you can write (note that the noise words 'but' and
       'on' are optional):

        check system myserver
          alert foo@bar but not on { instance }
          ...

       instead of:

          alert foo@bar on { change
                             checksum
                             data
                             exec
                             gid
                             icmp
                             invalid
                             match
                             nonexist
                             permission
                             size
                             timeout
                             timestamp }

       This will enable all alerts for foo@bar, except the monit instance
       related alerts.

       Event filtering can be used to send a mail to different email addresses
       depending on the events that occurred. For instance:

        alert foo@bar { nonexist, timeout, resource, icmp, connection }
        alert security@bar on { checksum, permission, uid, gid }
        alert manager@bar

       This will send an alert message to foo@bar whenever a nonexist,
       timeout, resource or connection problem occurs and a message to
       security@bar if a checksum, permission, uid or gid problem occurs. And
       finally, a message to manager@bar whenever any error event occurs.

       This is the list of events you can use in a mail-filter: uid, gid,
       size, nonexist, data, icmp, instance, invalid, exec, changed, timeout,
       resource, checksum, match, timestamp, connection, permission

       You can also disable the alerts localy using the NOALERT statement.
       This is useful for example when you have lot of services monitored,
       used the global alert statement, but don't want  to receive alerts for
       some minor subset of services:

        noalert appadmin@bar

       For example when you will place the noalert statement to the 'check
       system', the given user won't receive the system related alerts (such
       as monit instance started/stopped/reloaded alert, system overloaded
       alert, etc.) but will receive the alerts for all other monitored
       services.

       The following example will alert foo@bar on all events on all services
       by default, except the service mybar which will send an alert only on
       timeout. The trick is based on the fact that local definition of the
       same recipient overrides the global setting (including registered
       events and mail format):

        set alert foo@bar

        check process myfoo with pidfile /var/run/myfoo.pid
          ...
        check process mybar with pidfile /var/run/mybar.pid
          alert foo@bar only on { timeout }

       The 'instance' alert type report events related to monit internals,
       such as when a monit instance was started, stopped or reloaded.

       If the MTA (mailserver) for sending alerts is not available, monit can
       queue events on the local file-system until the MTA recover. Monit will
       then post queued events in order with their original timestamp so the
       events are not lost. This feature is most useful if monit is used
       together with e.g. m/monit and when event history is important.

       Alert message layout

       monit provides a default mail message layout that is short and to the
       point. Here's an example of a standard alert mail sent by monit:

        From: monit@tildeslash.com
        Subject: monit alert -- Does not exist apache
        To: hauk@tildeslash.com
        Date: Thu, 04 Sep 2003 02:33:03 +0200

        Does not exist Service apache

               Date:   Thu, 04 Sep 2003 02:33:03 +0200
               Action: restart
               Host:   www.tildeslash.com

        Your faithful employee,
        monit

       If you want to, you can change the format of this message with the
       optional mail-format statement. The syntax for this statement is as
       follows:

        mail-format {
             from: monit@localhost
          subject: $SERVICE $EVENT at $DATE
          message: Monit $ACTION $SERVICE at $DATE on $HOST: $DESCRIPTION.
                   Yours sincerely,
                   monit
        }

       Where the keyword from: is the email address monit should pretend it is
       sending from. It does not have to be a real mail address, but it must
       be a proper formated mail address, on the form: name@domain. The
       keyword subject: is for the email subject line. The subject must be on
       only one line. The message: keyword denotes the mail body. If used,
       this keyword should always be the last in a mail-format statement.  The
       mail body can be as long as you want and must not contain the '}'
       character.

       All of these format keywords are optional but you must provide at least
       one. Thus if you only want to change the from address monit is using
       you can do:

        set alert foo@bar with mail-format { from: bofh@bar.baz }

       From the previous example you will notice that some special $XXX
       variables was used. If used, they will be substituted and expanded into
       the text with these values:

       * $EVENT
            A string describing the event that occurred. The values are
            fixed and are:

            Event:    | Failure state:          | Recovery state:
            ---------------------------------------------------------------
            CHANGED   | "Changed"               | "Changed back"
            CHECKSUM  | "Checksum failed"       | "Checksum passed"
            CONNECTION| "Connection failed"     | "Connection passed"
            DATA      | "Data access error"     | "Data access succeeded"
            EXEC      | "Execution failed"      | "Execution succeeded"
            GID       | "GID failed"            | "GID passed"
            ICMP      | "ICMP failed"           | "ICMP passed"
            INSTANCE  | "Monit instance changed"| "Monit instance changed not"
            INVALID   | "Invalid type"          | "Type passed"
            MATCH     | "Regex match"           | "No regex match"
            NONEXIST  | "Does not exist"        | "Exists"
            PERMISSION| "Permission failed"     | "Permission passed"
            RESOURCE  | "Resource limit matched"| "Resource limit passed"
            SIZE      | "Size failed"           | "Size passed"
            TIMEOUT   | "Timeout"               | "Timeout recovery"
            TIMESTAMP | "Timestamp failed"      | "Timestamp passed"
            UID       | "UID failed"            | "UID passed"

       * $SERVICE
            The service entry name in monitrc

       * $DATE
            The current time and date (RFC 822 date style).

       * $HOST
            The name of the host monit is running on

       * $ACTION
            The name of the action which was done. Action names are fixed
            and are:

            Action:  | Name:
            --------------------
            ALERT    | "alert"
            EXEC     | "exec"
            MONITOR  | "monitor"
            RESTART  | "restart"
            START    | "start"
            STOP     | "stop"
            UNMONITOR| "unmonitor"

       * $DESCRIPTION
            The description of the error condition

       Setting a global mail format

       It is possible to set a standard mail format with the following global
       set-statement (keywords are in capital):

       SET MAIL-FORMAT {mail-format}

       Format set with this statement will apply to every alert statement that
       does not have its own specified mail-format.  This statement is most
       useful for setting a default from address for messages sent by monit,
       like so:

        set mail-format { from: monit@foo.bar.no }

       Setting a error reminder

       Monit by default sends just one error notification when the service
       failed and another one when it has recovered. If you want to be
       notified more then once in the case that the service remains failed,
       you can use the reminder option of alert statement (keywords are in
       capital):

       ALERT ... [WITH] REMINDER [ON] number [CYCLES]

       For example if you want to be notified each tenth cycle when the
       service remains failed, you can use:

         alert foo@bar with reminder on 10 cycles

       If you want to be notified on each failed cycle, you can use:

         alert foo@bar with reminder on 1 cycle

       Setting a mail server for alert messages

       The mail server monit should use to send alert messages is defined with
       a global set statement (keywords are in capital and optional statements
       in [brackets]):

        SET MAILSERVER {hostname|ip-address [PORT port]
                       [USERNAME username] [PASSWORD password]
                       [using SSLV2|SSLV3|TLSV1] [CERTMD5 checksum]}+
                       [with TIMEOUT X SECONDS]

       The port statement allows to use SMTP servers other then those
       listening on port 25. If omitted, port 25 is used when ssl is not
       enabled or tls is used, otherwise 465 is used by default (for ssl v2
       and v3).

       Monit support plain smtp authentication - you can set the username and
       password using USERNAME and PASSWORD options.

       To use the secure communication, use the SSLV2, SSLV3 or TLSV1 options,
       you can also specify the server certificate checksum using CERTMD5
       option.

       As you can see, it is possible to set several SMTP servers. If monit
       cannot connect to the first server in the list it will try the second
       server and so on. Monit has a default 5 seconds connection timeout and
       if the SMTP server is slow, monit could timeout when connecting or
       reading from the server.  You can use the optional timeout statement to
       explicit set the timeout to a higher value if needed. Here is an
       example for setting several mail servers:

        set mailserver mail.tildeslash.com,
                       mail.foo.bar port 10025 username "Rabbi" password "Loewe" using tlsv1,
                       localhost
                       with timeout 15 seconds

       Here monit will first try to connect to the server
       "mail.tildeslash.com", if this server is down monit will try
       "mail.foo.bar" on port 10025 using the given credentials via tls and
       finally "localhost". We do also set an explicit connect and read
       timeout; If monit cannot connect to the first SMTP server in the list
       within 15 seconds it will try the next server and so on.  The set
       mailserver .. statement is optional and if not defined monit defaults
       to use localhost as the SMTP server.

       Event queue

       Monit provide optionally queueing of event alerts that cannot be sent.
       For example, if no mail-server is available at the moment, monit can
       store events in a queue and try to reprocess them at the next cycle. As
       soon as the mail-server recover, monit will post the queued events. The
       queue is persistent across monit restarts and provided that the back-
       end filesystem is persistent too, across system restart as well.

       By default, the queue is disabled and if the alert handler fails, monit
       will simply drop the alert message. To enable the event queue, add the
       following statement to the monit control file:

        SET EVENTQUEUE BASEDIR <path> [SLOTS <number>]

       The <path> is the path to the directory where events will be stored.
       Optionally if you want to limit the queue size (maximum events count),
       use the slots option. If the slots option is not used, monit will store
       as many events as the backend filesystem allows.

       Example:

         set eventqueue
             basedir /var/monit
             slots 5000

       The events are stored in binary format, one file per event. The file
       size is ca. 130 bytes or a bit more (depending on the message length).
       The file name is composed of the unix timestamp, underscore and the
       service name, for example:

        /var/monit/1131269471_apache

       If you are running more then one monit instance on the same machine,
       you must use separated event queue directories to avoid sending wrong
       alerts to the wrong addresses.

       If you want to purge the queue by hand (remove queued event-files),
       monit should be stopped before the removal.

SERVICE TIMEOUT
       monit provides a service timeout mechanism for situations where a
       service simply refuses to start or respond over a longer period. In
       cases like this, and particularly if monit's poll-cycle is low, monit
       will simply increase the machine load by trying to restart the service.

       The timeout mechanism monit provides is based on two variables, i.e.
       the number the service has been started and the number of poll-cycles.
       For example, if a service had x restarts within y poll-cycles (where x
       <= y) then monit will timeout and not (re)start the service on the next
       cycle. If a timeout occurs monit will send you an alert message if you
       have register interest for this event.

       The syntax for the timeout statement is as follows (keywords are in
       capital):

       IF NUMBER RESTART NUMBER CYCLE(S) THEN TIMEOUT

       Where the first number is the number of service restarts and the
       second, the number of poll-cycles. If the number of cycles was reached
       without a timeout, the service start-counter is reset to zero. This
       provides some granularity to catch exceptional cases and do a service
       timeout, but let occasional service start and restarts happen without
       having an accumulated timeout.

       Here is an example where monit will timeout (not check the service) if
       the service was restarted 2 times within 3 cycles:

        if 2 restarts within 3 cycles then timeout

       To have monit check the service again after a timeout, run 'monit
       monitor service' from the command line. This will remove the timeout
       lock in the daemon and make the daemon start and check the service
       again.

SERVICE TESTS
       Monit provides several tests you may utilize in a service entry to test
       a service. Basically here are two classes of tests: variable and
       constant object tests.

       Constant object tests are related to failed/passed state.  In the case
       of error, monit will watch whether the failed parameter will recover -
       in such case it will handle recovery related action. General format:

       IF <TEST> [[<X>] [TIMES WITHIN] <Y> CYCLES] THEN ACTION [ELSE IF PASSED
       [[<X>] [TIMES WITHIN] <Y> CYCLES] THEN ACTION]

       For constant object tests if the <TEST> should validate to true, then
       the selected action is executed each cycle the condition remains true.
       The value for comparison is constant. Recovery action is evaluated only
       once (on failed->passed state change only). The 'ELSE IF PASSED' part
       is optional - if omitted, monit will do alert action on recovery by
       default. The alert is delivered only once on each state change unless
       overridden by 'reminder' alert option.

       Variable object tests begins with 'IF CHANGED' statement and serves for
       monitoring of object, which property can change legally - monit watches
       whether the value will change again. You can use it just for alert or
       to involve some automatic action, as for example to reload monitored
       process after its configuration file was changed.  Variable tests are
       supported for 'checksum', 'size', 'pid, 'ppid' and 'timestamp' tests
       only, if you consider that other tests can be useful in variable form
       too, please let us know.

       IF CHANGED <TEST> [[<X>] [TIMES WITHIN] <Y> CYCLES] THEN ACTION

       For variable object tests if the <TEST> should validate to true, then
       the selected action is executed once and monit will watch for another
       change. The value for comparison is a variable where the last result
       becomes the actual value, which is compared in future cycles. The alert
       is delivered each time the condition becomes true.

       You can restrict the event ratio needed to change the state:

       ... [[<X>] [TIMES WITHIN] <Y> CYCLES] ...

       This part is optional and is supported by all testing rules.  It
       defines how many event occurrences during how many cycles are needed to
       trigger the following action. You can use it in several ways - the core
       syntax is:

        [<X>] <Y> CYCLES

       It is possible to use filling words which give the rule better first-
       sight sense. You can use any filling words such as: FOR, TIMES, WITHIN,
       thus for example:

        if failed port 80 for 3 times within 5 cycles then alert

       or

        if failed port 80 for 10 cycles then unmonitor

       When you don't specify the <X>, it equals to <Y> by default, thus the
       rule applies when <Y> consecutive cycles of inverse event occurred
       (relatively to the current service state).

       When you omit it at all, monit will by default change state on first
       inverse event, which is equivalent to this notation:

        1 times within 1 cycles

       It is possible to use this option for failed, passed/recovered or
       changed rules. More complex examples:

        check device rootfs with path /dev/hda1
         if space usage > 80% 5 times within 15 cycles
            then alert
            else if passed for 10 cycles then alert
         if space usage > 90% for 5 cycles then
            exec '/try/to/free/the/space'
         if space usage > 99% then exec '/stop/processess'

       Note that the maximal cycles count which can be used in the rule is
       limited by the size of 'long long' data type on your platform.  This
       provides 64 cycles on usual platforms currently. In the case that you
       use unsupported value, the configuration parser will tell you the
       limits during monit startup.

       You must select an action to be executed from this list:

       o   ALERT sends the user an alert event on each state change (for
           constant object tests) or on each change (for variable object
           tests).

       o   RESTART restarts the service and sends an alert. Restart is
           conducted by first calling the service's registered stop method and
           then the service's start method.

       o   START starts the service by calling the service's registered start
           method and send an alert.

       o   STOP stops the service by calling the service's registered stop
           method and send an alert. If monit stops a service it will not be
           checked by monit anymore nor restarted again later. To reactivate
           monitoring of the service again you must explicitly enable
           monitoring from the web interface or from the console, e.g. 'monit
           monitor apache'.

       o   EXEC may be used to execute an arbitrary program and send an alert.
           If you choose this action you must state the program to be executed
           and if the program require arguments you must enclose the program
           and its arguments in a quoted string. You may optionally specify
           the uid and gid the executed program should switch to upon start.
           For instance:

            exec "/usr/local/tomcat/bin/startup.sh"
                 as uid nobody and gid nobody

           This may be useful if the program to be started cannot change to a
           lesser privileged user and group. This is typically needed for Java
           Servers. Remember, if monit is run by the superuser, then all
           programs executed by monit will be started with superuser
           privileges unless the uid and gid extension was used.

       o   MONITOR will enable monitoring of the service and send an alert.

       o   UNMONITOR will disable monitoring of the service and send an alert.
           The service will not be checked by monit anymore nor restarted
           again later.  To reactivate monitoring of the service you must
           explicitly enable monitoring from monit's web interface or from the
           console using the monitor argument.

       RESOURCE TESTING

       Monit can examine how much system resources a services are using. This
       test may only be used within a system or process service entry in the
       monit control file.

       Depending on the system or process characteristics, services can be
       stopped or restarted and alerts can be generated. Thus it is possible
       to utilize systems which are idle and to spare system under high load.

       The full syntax for the resource-statements used for resource testing
       is as follows (keywords are in capital and optional statements in
       [brackets]),

       IF resource operator value [[<X>] <Y> CYCLES] THEN action [ELSE IF
       PASSED [[<X>] <Y> CYCLES] THEN action]

       resource is a choice of "CPU", "CPU([user|system|wait])", "MEMORY",
       "CHILDREN", "TOTALMEMORY", "LOADAVG([1min|5min|15min])".  Some
       resources can be used inside of system service container, some in
       process service container and some in both:

       System only resource tests:

       CPU([user|system|wait]) is the percent of time that the system spend in
       user  or system/kernel space. Some systems such as linux 2.6 supports
       'wait' indicator as well.

       Process only resource tests:

       CPU is the CPU usage of the process and its children in parts of
       hundred (percent).

       CHILDREN is the number of child processes of the process.

       TOTALMEMORY is the memory usage of the process and its child processes
       in either percent or as an amount (Byte, kB, MB, GB).

       System and process resource tests:

       MEMORY is the memory usage of the system or in the process context of
       the process without its child processes in either percent (of the
       systems total) or as an amount (Byte, kB, MB, GB).

       LOADAVG([1min|5min|15min]) refers to the system's load average.  The
       load average is the number of processes in the system run queue,
       averaged over the specified time period.

       operator is a choice of "<", ">", "!=", "==" in C notation, "gt", "lt",
       "eq", "ne" in shell sh notation and "greater", "less", "equal",
       "notequal" in human readable form (if not specified, default is EQUAL).

       value is either an integer or a real number (except for CHILDREN). For
       CPU, MEMORY and TOTALMEMORY you need to specify a unit.  This could be
       "%" or if applicable "B" (Byte), "kB" (1024 Byte), "MB" (1024 KiloByte)
       or "GB" (1024 MegaByte).

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       To calculate the cycles, a counter is raised whenever the expression
       above is true and it is lowered whenever it is false (but not below 0).
       All counters are reset in case of a restart.

       The following is an example to check that the CPU usage of a service is
       not going beyond 50% during five poll cycles. If it does, monit will
       restart the service:

        if cpu is greater than 50% for 5 cycles then restart

       See also the example section below.

       FILE CHECKSUM TESTING

       The checksum statement may only be used in a file service entry. If
       specified in the control file, monit will compute a md5 or sha1
       checksum for a file.

       The checksum test in constant form is used to verify that a file does
       not change. Syntax (keywords are in capital):

       IF FAILED [MD5|SHA1] CHECKSUM [EXPECT checksum] [[<X>] <Y> CYCLES] THEN
       action [ELSE IF PASSED [[<X>] <Y> CYCLES] THEN action]

       The checksum test in variable form is used to watch for file changes.
       Syntax (keywords are in capital):

       IF CHANGED [MD5|SHA1] CHECKSUM [[<X>] <Y> CYCLES] THEN action

       The choice of MD5 or SHA1 is optional. MD5 features a 256 bit and SHA1
       a 320 bit checksum. If this option is omitted monit tries to guess the
       method from the EXPECT string or uses MD5 as default.

       expect is optional and if used it specifies a md5 or sha1 string monit
       should expect when testing a file's checksum. If expect is used, monit
       will not compute an initial checksum for the file, but instead use the
       string you submit. For example:

        if failed checksum and
           expect the sum 8f7f419955cefa0b33a2ba316cba3659
        then alert

       You can, for example, use the GNU utility md5sum(1) or sha1sum(1) to
       create a checksum string for a file and use this string in the
       expect-statement.

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       The checksum statement in variable form may be used to check a file for
       changes and if changed, do a specified action.  For instance to reload
       a server if its configuration file was changed. The following
       illustrate this for the apache web server:

        check file httpd.conf path /usr/local/apache/conf/httpd.conf
            if changed sha1 checksum
               then exec "/usr/local/apache/bin/apachectl graceful"

       If you plan to use the checksum statement for security reasons, (a very
       good idea, by the way) and to monitor a file or files which should not
       change, then please use constant form and also read the DEPENDENCY TREE
       section below to see a detailed example on how to do this properly.

       Monit can also test the checksum for files on a remote host via the
       HTTP protocol. See the CONNECTION TESTING section below.

       TIMESTAMP TESTING

       The timestamp statement may only be used in a file, fifo or directory
       service entry.

       The timestamp test in constant form is used to verify various timestamp
       conditions. Syntax (keywords are in capital):

       IF TIMESTAMP [[operator] value [unit]] [[<X>] <Y> CYCLES] THEN action
       [ELSE IF PASSED [[<X>] <Y> CYCLES] THEN action]

       The timestamp statement in variable form is simply to test an existing
       file or directory for timestamp changes and if changed, execute an
       action. Syntax (keywords are in capital):

       IF CHANGED TIMESTAMP [[<X>] <Y> CYCLES] THEN action

       operator is a choice of "<", ">", "!=", "==" in C notation, "GT", "LT",
       "EQ", "NE" in shell sh notation and "GREATER", "LESS", "EQUAL",
       "NOTEQUAL" in human readable form (if not specified, default is EQUAL).

       value is a time watermark.

       unit is either "SECOND", "MINUTE", "HOUR" or "DAY" (it is also possible
       to use "SECONDS", "MINUTES", "HOURS", or "DAYS").

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       The variable timestamp statement is useful for checking a file for
       changes and then execute an action. This version was written
       particularly with configuration files in mind. For instance, if you
       monitor the apache web server you can use this statement to reload
       apache if the httpd.conf (apache's configuration file) was changed.
       Like so:

        check file httpd.conf with path /usr/local/apache/conf/httpd.conf
          if changed timestamp
             then exec "/usr/local/apache/bin/apachectl graceful"

       The constant timestamp version is useful for monitoring systems able to
       report its state by changing the timestamp of certain state files. For
       instance the iPlanet Messaging server stored process system updates the
       timestamp of:

        o stored.ckp
        o stored.lcu
        o stored.per

       If a task should fail, the system keeps the timestamp. To report stored
       problems you can use the following statements:

        check file stored.ckp with path /msg-foo/config/stored.ckp
          if timestamp > 1 minute then alert

        check file stored.lcu with path /msg-foo/config/stored.lcu
          if timestamp > 5 minutes then alert

        check file stored.per with path /msg-foo/config/stored.per
          if timestamp > 1 hour then alert

       As mentioned above, you can also use the timestamp statement for
       monitoring directories for changes. If files are added or removed from
       a directory, its timestamp is changed:

        check directory mydir path /foo/directory
         if timestamp > 1 hour then alert

       or

        check directory myotherdir path /foo/secure/directory
         if timestamp < 1 hour then alert

       The following example is a hack for restarting a process after a
       certain time. Sometimes this is a necessary workaround for some third-
       party applications, until the vendor fix a problem:

        check file server.pid path /var/run/server.pid
              if timestamp > 7 days
                 then exec "/usr/local/server/restart-server"

       FILE SIZE TESTING

       The size statement may only be used in a file service entry.  If
       specified in the control file, monit will compute a size for a file.

       The size test in constant form is used to verify various size
       conditions. Syntax (keywords are in capital):

       IF SIZE [[operator] value [unit]] [[<X>] <Y> CYCLES] THEN action [ELSE
       IF PASSED [[<X>] <Y> CYCLES] THEN action]

       The size statement in variable form is simply to test an existing file
       for size changes and if changed, execute an action. Syntax (keywords
       are in capital):

       IF CHANGED SIZE [[<X>] <Y> CYCLES] THEN action

       operator is a choice of "<", ">", "!=", "==" in C notation, "GT", "LT",
       "EQ", "NE" in shell sh notation and "GREATER", "LESS", "EQUAL",
       "NOTEQUAL" in human readable form (if not specified, default is EQUAL).

       value is a size watermark.

       unit is a choice of "B","KB","MB","GB" or long alternatives "byte",
       "kilobyte", "megabyte", "gigabyte". If it is not specified, "byte" unit
       is assumed by default.

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       The variable size test form is useful for checking a file for changes
       and send an alert or execute an action. Monit will register the size of
       the file at startup and monitor the file for changes. As soon as the
       value changed, monit will do specified action, reset the registered
       value to new result and continue to monitor, whether the size changed
       again.

       One example of use for this statement is to conduct security checks,
       for instance:

        check file su with path /bin/su
              if changed size then exec "/sbin/ifconfig eth0 down"

       which will "cut the cable" and stop a possible intruder from
       compromising the system further. This test is just one of many you may
       use to increase the security awareness on a system. If you plan to use
       monit for security reasons we recommend that you use this test in
       combination with other supported tests like checksum, timestamp, and so
       on.

       The constant size test form may be useful in similar or different
       contexts. It can, for instance, be used to test if a certain file size
       was exceeded and then alert you or monit may execute a certain action
       specified by you. An example is to use this statement to rotate log
       files after they have reached a certain size or to check that a
       database file does not grow beyond a specified threshold.

       To rotate a log file:

        check file myapp.log with path /var/log/myapp.log
           if size > 50 MB then
              exec "/usr/local/bin/rotate /var/log/myapp.log myapp"

       where /usr/local/bin/rotate may be a simple script, such as:

        #/bin/bash
        /bin/mv $1 $1.`date +%y-%m-%d`
        /usr/bin/pkill -HUP $2

       Or you may use this statement to trigger the logrotate(8) program, to
       do an "emergency" rotate. Or to send an alert if a file becomes a known
       bottleneck if it grows behind a certain size because of limits in a
       database engine:

        check file mydb with path /data/mydatabase.db
              if size > 1 GB then alert

       This is a more restrictive form of the first example where the size is
       explicitly defined (note that the real su size is system dependent):

        check file su with path /bin/su
              if size != 95564 then exec "/sbin/ifconfig eth0 down"

       FILE CONTENT TESTING

       The match statement allows you to test the content of a text file by
       using regular expressions. This is a great feature if you need to
       periodically test files, such as log files, for certain patterns. If a
       pattern match, monit defaults to raise an alert, other actions are also
       possible.

       The syntax (keywords in capital) for using this function is:

       IF [NOT] MATCH {regex|path} [[<X>] <Y> CYCLES] THEN action

       regex is a string containing the extended regular expression.  See also
       regex(7).

       path is an absolute path to a file containing extended regular
       expression on every line. See also regex(7).

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       You can use the NOT statement to invert a match.

       The content is only being checked every cycle. If content is being
       added and removed between two checks they are unnoticed.

       On startup the read position is set to the end of the file and monit
       continue to scan to the end of file on each cycle.  But if the file
       size should decrease or inode change the read position is set to the
       start of the file.

       Only lines ending with a newline character are inspected. Thus, lines
       are being ignored until they have been completed with this character.
       Also note that only the first 511 characters of a line are inspected.

       IGNORE [NOT] MATCH {regex|path}

       Lines matching an IGNORE are not inspected during later evaluations.
       IGNORE MATCH has always precedence over IF MATCH.

       All IGNORE MATCH statements are evaluated first, in the order of their
       appearance. Thereafter, all the IF MATCH statements are evaluated.

       A real life example might look like this:

         check file syslog with path /var/log/syslog
           ignore match
               "^\w{3} [ :0-9]{11} [._[:alnum:]-]+ monit\[[0-9]+\]:"
           ignore match /etc/monit/ignore.regex
           if match
               "^\w{3} [ :0-9]{11} [._[:alnum:]-]+ mrcoffee\[[0-9]+\]:"
           if match /etc/monit/active.regex then alert

       FILESYSTEM FLAGS TESTING

       monit tests the filesystem flags of devices for change. This test is
       implicit and monit will send alert in the case of failure by default.

       You may override the default action using below rule (it may only be
       used within a device service entry in the monit control file).

       This test is useful for detecting changes of the filesystem flags such
       as when the filesystem became read-only based on disk errors or the
       mount flags were changed (such as nosuid). Each platform provides
       different flags set. POSIX defined the RDONLY and NOSUID flags which
       should work on all platforms. Some platforms (such as FreeBSD) present
       another flags in addition.

       The syntax for the fsflags statement is:

       IF CHANGED FSFLAGS [[<X>] <Y> CYCLES] THEN action

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       Example:

        check device rootfs with path /
              if changed fsflags then exec "/my/script"
              alert root@localhost

       SPACE TESTING

       Monit can test devices/file systems and check for space usage. This
       test may only be used within a device service entry in the monit
       control file.

       Monit will check a device's total space usage. If you only want to
       check available space for non-superuser, you must set the watermark
       appropriately (i.e. total space minus reserved blocks for the
       superuser).

       You can obtain (and set) the superuser's reserved blocks size, for
       example by using the tune2fs utility on Linux. On Linux 5% of available
       blocks are reserved for the superuser by default. To list the reserved
       blocks for the superuser:

        [root@berry monit]# tune2fs -l /dev/hda1| grep "Reserved block"
        Reserved block count:     319994
        Reserved blocks uid:      0 (user root)
        Reserved blocks gid:      0 (group root)

       On solaris 10% of the blocks are reserved. You can also use tunefs on
       solaris to change values on a live filesystem.

       The full syntax for the space statement is:

       IF SPACE operator value unit [[<X>] <Y> CYCLES] THEN action [ELSE IF
       PASSED [[<X>] <Y> CYCLES] THEN action]

       operator is a choice of "<",">","!=","==" in c notation, "gt", "lt",
       "eq", "ne" in shell sh notation and "greater", "less", "equal",
       "notequal" in human readable form (if not specified, default is EQUAL).

       unit is a choice of "B","KB","MB","GB", "%" or long alternatives
       "byte", "kilobyte", "megabyte", "gigabyte", "percent".

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       INODE TESTING

       If supported by the file-system, you can use monit to test for inodes
       usage. This test may only be used within a device service entry in the
       monit control file.

       If the device becomes unavailable, monit will call the entry's
       registered start method, if it is defined and if monit is running in
       active mode. If monit runs in passive mode or the start methods is not
       defined, monit will just send an error alert.

       The syntax for the inode statement is:

       IF INODE(S) operator value [unit] [[<X>] <Y> CYCLES] THEN action [ELSE
       IF PASSED [[<X>] <Y> CYCLES] THEN action]

       operator is a choice of "<",">","!=","==" in c notation, "gt", "lt",
       "eq", "ne" in shell sh notation and "greater", "less", "equal",
       "notequal" in human readable form (if not specified, default is EQUAL).

       unit is optional. If not specified, the value is an absolute count of
       inodes. You can use the "%" character or the longer alternative
       "percent" as a unit.

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       PERMISSION TESTING

       Monit can monitor the permissions. This test may only be used within a
       file, fifo, directory or device service entry in the monit control
       file.

       The syntax for the permission statement is:

       IF FAILED PERM(ISSION) octalnumber [[<X>] <Y> CYCLES] THEN action [ELSE
       IF PASSED [[<X>] <Y> CYCLES] THEN action]

       octalnumber defines permissions for a file, a directory or a device as
       four octal digits (0-7). Valid range: 0000 - 7777 (you can ommit the
       leading zeros, monit will add the zeros to the left thus for example
       "640" is valid value and matches "0640").

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       The web interface will show a permission warning if the test failed.

       We recommend that you use the UNMONITOR action in a permission
       statement. The rationale for this feature is security and that monit
       does not start a possible cracked program or script. Example:

        check file monit.bin with path "/usr/local/bin/monit"
              if failed permission 0555 then unmonitor
              alert foo@bar

       If the test fails, monit will simply send an alert and stop monitoring
       the file and propagate an unmonitor action upward in a depend tree.

       UID TESTING

       monit can monitor the owner user id (uid). This test may only be used
       within a file, fifo, directory or device service entry in the monit
       control file.

       The syntax for the uid statement is:

       IF FAILED UID user [[<X>] <Y> CYCLES] THEN action [ELSE IF PASSED
       [[<X>] <Y> CYCLES] THEN action]

       user defines a user id either in numeric or in string form.

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       The web interface will show a uid warning if the test should fail.

       We recommend that you use the UNMONITOR action in a uid statement. The
       rationale for this feature is security and that monit does not start a
       possible cracked program or script. Example:

        check file passwd with path /etc/passwd
              if failed uid root then unmonitor
              alert root@localhost

       If the test fails, monit will simply send an alert and stop monitoring
       the file and propagate an unmonitor action upward in a depend tree.

       GID TESTING

       monit can monitor the owner group id (gid). This test may only be used
       within a file, fifo, directory or device service entry in the monit
       control file.

       The syntax for the gid statement is:

       IF FAILED GID user [[<X>] <Y> CYCLES] THEN action [ELSE IF PASSED
       [[<X>] <Y> CYCLES] THEN action]

       user defines a group id either in numeric or in string form.

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       The web interface will show a gid warning if the test should fail.

       We recommend that you use the UNMONITOR action in a gid statement. The
       rationale for this feature is security and that monit does not start a
       possible cracked program or script. Example:

        check file shadow with path /etc/shadow
              if failed gid root then unmonitor
              alert root@localhost

       If the test fails, monit will simply send an alert and stop monitoring
       the file and propagate an unmonitor action upward in a depend tree.

       PID TESTING

       monit tests the process id (pid) of processes for change. This test is
       implicit and monit will send alert in the case of failure by default.

       You may override the default action using below rule (it may only be
       used within a process service entry in the monit control file).

       The syntax for the pid statement is:

       IF CHANGED PID [[<X>] <Y> CYCLES] THEN action

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       This test is useful to detect possible process restarts which has
       occurred in the timeframe between two monit testing cycles.  In the
       case that the restart was fast and the process provides expected
       service (i.e. all tests passed) you will be notified that the process
       was replaced.

       For example sshd daemon can restart very quickly, thus if someone
       changes its configuration and do sshd restart outside of monit control,
       you will be notified that the process was replaced by new instance (or
       you can optionaly do some other action such as preventively stop sshd).

       Another example is MySQL Cluster which has its own watchdog with
       process restart ability. You can use monit for redundant monitoring.
       Monit will just send alert in the case that the MySQL cluster restarted
       the node quickly.

       Example:

        check process sshd with pidfile /var/run/sshd.pid
              if changed pid then exec "/my/script"
              alert root@localhost

       PPID TESTING

       monit tests the process parent id (ppid) of processes for change.  This
       test is implicit and monit will send alert in the case of failure by
       default.

       You may override the default action using below rule (it may only be
       used within a process service entry in the monit control file).

       The syntax for the ppid statement is:

       IF CHANGED PPID [[<X>] <Y> CYCLES] THEN action

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       This test is useful for detecting changes of a process parent.

       Example:

        check process myproc with pidfile /var/run/myproc.pid
              if changed ppid then exec "/my/script"
              alert root@localhost

       CONNECTION TESTING

       Monit is able to perform connection testing via networked ports or via
       Unix sockets. A connection test may only be used within a process or
       within a host service entry in the monit control file.

       If a service listens on one or more sockets, monit can connect to the
       port (using either tcp or udp) and verify that the service will accept
       a connection and that it is possible to write and read from the socket.
       If a connection is not accepted or if there is a problem with socket
       read/write, monit will assume that something is wrong and execute a
       specified action. If monit is compiled with openssl, then ssl based
       network services can also be tested.

       The full syntax for the statement used for connection testing is as
       follows (keywords are in capital and optional statements in
       [brackets]),

       IF FAILED [host] port [type] [protocol|{send/expect}+] [timeout] [[<X>]
       <Y> CYCLES] THEN action [ELSE IF PASSED [[<X>] <Y> CYCLES] THEN action]

       or for Unix sockets,

       IF FAILED [unixsocket] [type] [protocol|{send/expect}+] [timeout]
       [[<X>] <Y> CYCLES] THEN action [ELSE IF PASSED [[<X>] <Y> CYCLES] THEN
       action]

       host:HOST hostname. Optionally specify the host to connect to.  If the
       host is not given then localhost is assumed if this test is used inside
       a process entry. If this test was used inside a remote host entry then
       the entry's remote host is assumed.  Although host is intended for
       testing name based virtual host in a HTTP server running on local or
       remote host, it does allow the connection statement to be used to test
       a server running on another machine. This may be useful; For instance
       if you use Apache httpd as a front-end and an application-server as the
       back-end running on another machine, this statement may be used to test
       that the back-end server is running and if not raise an alert.

       port:PORT number. The port number to connect to

       unixsocket:UNIXSOCKET PATH. Specifies the path to a Unix socket.
       Servers based on Unix sockets, always runs on the local machine and
       does not use a port.

       type:TYPE {TCP|UDP|TCPSSL}. Optionally specify the socket type monit
       should use when trying to connect to the port. The different socket
       types are; TCP, UDP or TCPSSL, where TCP is a regular stream based
       socket, UDP is a datagram socket and TCPSSL specify that monit should
       use a TCP socket with SSL when connecting to a port. The default socket
       type is TCP. If TCPSSL is used you may optionally specify the SSL/TLS
       protocol to be used and the md5 sum of the server's certificate. The
       TCPSSL options are:

        TCPSSL [SSLAUTO|SSLV2|SSLV3|TLSV1] [CERTMD5 md5sum]

       proto(col):PROTO {protocols}. Optionally specify the protocol monit
       should speak when a connection is established. At the moment monit
       knows how to speak:
        APACHE-STATUS
        DNS
        DWP
        FTP
        HTTP
        IMAP
        CLAMAV
        LDAP2
        LDAP3
        MYSQL
        NNTP
        NTP3
        POP
        POSTFIX-POLICY
        RDATE
        RSYNC
        SMTP
        SSH
        TNS
        PGSQL If you have compiled monit with ssl support, monit can also
       speak the SSL variants such as:
        HTTPS
        FTPS
        POPS
        IMAPS To use the SSL protocol support you need to define the socket as
       SSL and use the general protocol name (for example in the case of
       HTTPS) :
        TYPE TCPSSL PROTOCOL HTTP If the server's protocol is not found in
       this list, simply do not specify the protocol and monit will utilize a
       default test, including testing if it is possible to read and write to
       the port. This default test is in most cases more than good enough to
       deduce if the server behind the port is up or not.

       The protocol statement is:

        [PROTO(COL) {name} [REQUEST {"/path"} [with CHECKSUM checksum]]

       As you can see, you may specify a request after the protocol, at the
       moment only the HTTP protocol supports the request option.  See also
       below for an example.

       In addition to the standard protocols, the APACHE-STATUS protocol is a
       test of a specific server type, rather than a generic protocol. Server
       performance is examined using the status page generated by Apache's
       mod_status, which is expected to be at its default address of
       http://www.example.com/server-status.  Currently the APACHE-STATUS
       protocol examines the percentage of Apache child processes which are

        o logging (loglimit)
        o closing connections (closelimit)
        o performing DNS lookups (dnslimit)
        o in keepalive with a client (keepalivelimit)
        o replying to a client (replylimit)
        o receiving a request (requestlimit)
        o initialising (startlimit)
        o waiting for incoming connections (waitlimit)
        o gracefully closing down (gracefullimit)
        o performing cleanup procedures (cleanuplimit)

       Each of these quantities can be compared against a value relative to
       the total number of active Apache child processes. If the comparison
       expression is true the chosen action is performed.

       The apache-status protocol statement is formally defined as (keywords
       in uppercase):

        PROTO(COL) {limit} OP PERCENT [OR {limit} OP PERCENT]*

       where {limit} is one or more of: loglimit, closelimit, dnslimit,
       keepalivelimit, replylimit, requestlimit, startlimit, waitlimit
       gracefullimit or cleanuplimit. The operator OP is one of: [<|=|>].

       You can combine all of these test into one expression or you can choose
       to test a certain limit. If you combine the limits you must or' them
       together using the OR keyword.

       Here's an example were we test for a loglimit more than 10 percent, a
       dnslimit over 25 percent and a wait limit less than 20 percent of
       processes. See also more examples below in the example section.

        protocol apache-status
                       loglimit > 10% or
                       dnslimit > 50% or
                       waitlimit < 20%
        then alert

       Obviously, do not use this test unless the httpd server you are testing
       is Apache Httpd and mod_status is activated on the server.

       send/expect: {SEND|EXPECT} "string" .... If monit does not support the
       protocol spoken by the server, you can write your own protocol-test
       using send and expect strings. The SEND statement sends a string to the
       server port and the EXPECT statement compares a string read from the
       server with the string given in the expect statement. If your system
       supports POSIX regular expressions, you can use regular expressions in
       the expect string, see regex(7) to learn more about the types of
       regular expressions you can use in an expect string. Otherwise the
       string is used as it is. The send/expect statement is:

        [{SEND|EXPECT} "string"]+

       Note that monit will send a string as it is, and you must remember to
       include CR and LF in the string sent to the server if the protocol
       expect such characters to terminate a string (most text based protocols
       used over Internet does). Likewise monit will read up to 256 bytes from
       the server and use this string when comparing the expect string. If the
       server sends strings terminated by CRLF, (i.e. "\r\n") you may remember
       to add the same terminating characters to the string you expect from
       the server.

       You can use non-printable characters in a send string if needed. Use
       the hex notation, \0xHEXHEX to send any char in the range \0x00-\0xFF,
       that is, 0-255 in decimal. This may be useful when testing some network
       protocols, particularly those over UDP. An example, to test a quake 3
       server you can use the following,

             send "\0xFF\0xFF\0xFF\0xFFgetstatus"
             expect "sv_floodProtect|sv_maxPing"

       Finally, send/expect can be used with any socket type, such as TCP
       sockets, UNIX sockets and UDP sockets.

       timeout:with TIMEOUT x SECONDS. Optionally specifies the connect and
       read timeout for the connection. If monit cannot connect to the server
       within this time it will assume that the connection failed and execute
       the specified action. The default connect timeout is 5 seconds.

       action is a choice of "ALERT", "RESTART", "START", "STOP", "EXEC",
       "MONITOR" or "UNMONITOR".

       Connection testing using the URL notation

       You can test a HTTP server using the compact URL syntax. This test also
       allow you to use POSIX regular expressions to test the content returned
       by the HTTP server.

       The full syntax for the URL statement is as follows (keywords are in
       capital and optional statements in [brackets]):

         IF FAILED URL ULR-spec
            [CONTENT {==|!=} "regular-expression"]
            [TIMEOUT number SECONDS] [[<X>] <Y> CYCLES]
            THEN action
            [ELSE IF PASSED [[<X>] <Y> CYCLES] THEN action]

       Where URL-spec is an URL on the standard form as specified in RFC 2396:

        <protocol>://<authority><path>?<query>

       Here is an example on an URL where all components are used:

        http://user:password@www.foo.bar:8080/document/?querystring#ref

       If a username and password is included in the URL monit will attempt to
       login at the server using Basic Authentication.

       Testing the content returned by the server is optional. If used, you
       can test if the content match or does not match a regular expression.
       Here's an example on how the URL statement can be used in a check
       service:

        check host FOO with address www.foo.bar
             if failed url
                http://user:password@www.foo.bar:8080/?querystring
                and content == 'action="j_security_check"'
             then ...

       Monit will look at the content-length header returned by the server and
       download this amount before testing the content. That is, if the
       content-length is more than 1Mb or this header is not set by the server
       monit will default to download up to 1 Mb and not more.

       Only the http(s) protocol is supported in an URL statement. If the
       protocol is https monit will use SSL when connecting to the server.

       Remote host ping test

       In addition monit can perform ICMP Echo tests in remote host checks.
       The icmp test may only be used in a check host entry and monit must run
       with super user privileges, that is, the root user must run monit. The
       reason is that the icmp test utilize a raw socket to send the icmp
       packet and only the super user is allowed to create a raw socket.

       The full syntax for the ICMP Echo statement used for ping testing is as
       follows (keywords are in capital and optional statements in
       [brackets]):

         IF FAILED ICMP TYPE ECHO
            [COUNT number] [WITH] [TIMEOUT number SECONDS]
              [[<X>] <Y> CYCLES]
            THEN action
            [ELSE IF PASSED [[<X>] <Y> CYCLES] THEN action]

       The rules for action and timeout are the same as those mentioned above
       in the CONNECTION TESTING section. The count parameter specifies how
       many consecutive echo requests will be send to the host in one cycle.
       In the case that no reply came within timeout frame, monit reports
       error. When at least one reply was received, the test will pass. Monit
       sends by default three echo requests in one cycle to prevent the random
       packet loss from generating false alarm (i.e. up to 66% packet loss is
       tolerated). You can set the count option to a value between 1 and 20,
       which can serve as an error ratio. For example if you require 100% ping
       success, set the count to 1 (i.e. just one request will be sent, and if
       the packet was lost an error will be reported).

       An icmp ping test is useful for testing if a host is up, before testing
       ports at the host. If an icmp ping test is used in a check host entry,
       this test is run first and if the ping test should fail we assume that
       the connection to the host is down and monit does not continue to test
       any ports. Here's an example:

        check host xyzzy with address xyzzy.org
              if failed icmp type echo count 5 with timeout 15 seconds
                 then alert
              if failed port 80 proto http then alert
              if failed port 443 type TCPSSL proto http then alert
              alert foo@bar

       In this case, if the icmp test should fail you will get one alert and
       only one alert as long as the host is down, and equally important,
       monit will not test port 80 and port 443. Likewise if the icmp ping
       test should succeed (again) monit will continue to test both port 80
       and 443.

       Keep in mind though that some firewalls can block icmp packages and
       thus render the test useless.

       Examples

       To check a port connection and receive an alert if monit cannot connect
       to the port, use the following statement:

         if failed port 80 then alert

       In this case the machine in question is assumed to be the default host.
       For a process entry it's localhost and for a remote host entry it's the
       address of the remote host. Monit will conduct a tcp connection to the
       host at port 80 and use tcp by default.  If you want to connect with
       udp, you can specify this after the port-statement;

        if failed port 53 type udp protocol dns then alert

       Monit will stop trying to connect to the port after 5 seconds and
       assume that the server behind the port is down. You may increase or
       decrease the connect timeout by explicit add a connection timeout. In
       the following example the timeout is increased to 15 seconds and if
       monit cannot connect to the server within 15 seconds the test will fail
       and an alert message is sent.

         if failed port 80 with timeout 15 seconds then alert

       If a server is listening to a Unix socket the following statement can
       be used:

        if failed unixsocket /var/run/sophie then alert

       A Unix socket is used by some servers for fast (interprocess)
       communication on localhost only. A Unix socket is specified by a path
       and in the example above the path, /var/run/sophie, specifies a Unix
       socket.

       If your machine answers for several virtual hosts you can prefix the
       port statement with a host-statement like so:

        if failed host www.sol.no port 80 then alert
        if failed host 80.69.226.133 port 443 then alert
        if failed host kvasir.sol.no port 80 then alert

       And as mentioned above, if you do not specify a host-statement,
       localhost or address is assumed.

       Monit also knows how to speak some of the more popular Internet
       protocols. So, besides testing for connections, monit can also speak
       with the server in question to verify that the server works. For
       example, the following is used to test a http server:

        if failed host www.tildeslash.com port 80 proto http
           then restart

       Some protocols also support a request statement. This statement can be
       used to ask the server for a special document entity.

       Currently only the HTTP protocol module supports the request statement,
       such as:

        if failed host www.myhost.com port 80 protocol http
           and request "/data/show.php?a=b&c=d"
        then restart

       The request must contain an URI string specifying a document from the
       http server. The string will be URL encoded by monit before it sends
       the request to the http server, so it's okay to use URL unsafe
       characters in the request. If the request statement isn't specified,
       the default web server page will be requested.

       You can also test the checksum for documents returned by a http server.
       You can use either MD5 sums:

        if failed port 80 protocol http
           and request "/page.html"
               with checksum 8f7f419955cefa0b33a2ba316cba3659
        then alert

       Or you can use SHA1 sums:

        if failed port 80 protocol http
           and request "/page.html"
               with checksum e428302e260e0832007d82de853aa8edf19cd872
        then alert

       monit will compute a checksum (either MD5 or SHA1 is used, depending on
       length of the hash) for the document (in the above case, /page.html)
       and compare the computed checksum with the expected checksum. If the
       sums does not match then the if-tests action is performed, in this case
       alert. Note that monit will not test the checksum for a document if the
       server does not set the HTTP Content-Length header. A HTTP server
       should set this header when it server a static document (i.e. a file).
       A server will often use chunked transfer encoding instead when serving
       dynamic content (e.g. a document created by a CGI-script or a Servlet),
       but to test the checksum for dynamic content is not very useful. There
       are no limitation on the document size, but keep in mind that monit
       will use time to download the document over the network so it's
       probably smart not to ask monit to compute a checksum for documents
       larger than 1Mb or so, depending on you network connection of course.
       Tip; If you get a checksum error even if the document has the correct
       sum, the reason may be that the download timed out. In this case,
       explicit set a longer timeout than the default 5 seconds.

       As mentioned above, if the server protocol is not supported by monit
       you can write your own protocol test using send/expect strings. Here we
       show a protocol test using send/expect for an imaginary "Ali Baba and
       the Forty Thieves" protocol:

        if failed host cave.persia.ir port 4040
           send "Open, Sesame!\r\n"
           expect "Please enter the cave\r\n"
           send "Shut, Sesame!\r\n"
           expect "See you later [A-Za-z ]+\r\n"
        then restart

       The TCPSSL statement can optionally test the md5 sum of the server's
       certificate. You must state the md5 certificate string you expect the
       server to deliver and upon a connect to the server, the server's actual
       md5 sum certificate string is tested.  Any other symbol but [A-Fa-f0-9]
       is being ignored in that sting.  Thus it is possible to copy and paste
       the output of e.g. openssl.  If they do not match, the connection test
       fails. If the ssl version handshake does not work properly you can also
       force a specific ssl version, as we demonstrate in this example:

        if failed host shop.sol.no port 443
           type TCPSSL SSLV3 # Force monit to use ssl version 3
           # We expect the server to return this  md5 certificate sum
           # as either 12-34-56-78-90-AB-CD-EF-12-34-56-78-90-AB-CD-EF
           # or e.g.   1234567890ABCDEF1234567890ABCDEF
           # or e.g.   1234567890abcdef1234567890abcdef
           # what ever come in more handy (see text above)
           CERTMD5 12-34-56-78-90-AB-CD-EF-12-34-56-78-90-AB-CD-EF
           protocol http
        then restart

       Here's an example where a connection test is used inside a process
       entry:

        check process apache with pidfile /var/run/apache.pid
              start program = "/etc/init.d/httpd start"
              stop program = "/etc/init.d/httpd stop"
              if failed host www.tildeslash.com port 80 then restart

       Here, a connection test is used in a remote host entry:

        check host up2date with address ftp.redhat.com
              if failed port 21 and protocol ftp then alert

       Since we did not explicit specify a host in the above test, monit will
       connect to port 21 at ftp.redhat.com. Apropos, the host address can be
       specified as a dotted IP address string or as hostname in the DNS. The
       following is exactly[*] the same test, but here an ip address is used
       instead:

        check host up2date with address 66.187.232.30
              if failed port 21 and protocol ftp then alert

       [*] Well, not quite, since we specify an ip-address directly we will
       bypass any DNS round-robin setup, but that's another story.

       For more examples, see the example section below.

MONIT HTTPD
       If specified in the control file, monit will start a monit daemon with
       http support. From a Browser you can then start and stop services,
       disable or enable service monitoring as well as view the status of each
       service. Also, if monit logs to its own file, you can view the content
       of this logfile in a Browser.

       The control file statement for starting a monit daemon with http
       support is a global set-statement:

       set httpd port 2812

       And you can use this URL, http://localhost:2812/, to access the daemon
       from a browser. The port number, in this case 2812, can be any number
       that you are allowed to bind to.

       If you have compiled monit with openssl, you can also start the httpd
       server with ssl support, using the following expression:

        set httpd port 2812
            ssl enable
            pemfile /etc/certs/monit.pem

       And you can use this URL, https://localhost:2812/, to access the monit
       web server over an ssl encrypted connection.

       The pemfile, in the example above, holds both the server's private key
       and certificate. This file should be stored in a safe place on the
       filesystem and should have strict permissions, that is, no more than
       0700.

       In addition, if you want to check for client certificates you can use
       the CLIENTPEMFILE statement. In this case, a connecting client has to
       provided a certificate known by monit in order to connect. This file
       also needs to have all necessary CA certificates. A configuration could
       look like:

        set httpd port 2812
            ssl enable
            pemfile /etc/certs/monit.pem
            clientpemfile /etc/certs/monit-client.pem

       By default self signed client certificates are not allowed. If you want
       to use a self signed certificate from a client it has to be allowed
       explicitly with the ALLOWSELFCERTIFICATION statement.

       For more information on how to use monit with SSL and for more
       information about certificates and generating pem files, please consult
       the README.SSL file accompanying the software.

       If you only want the http server to accept connect requests to one host
       addresses you can specify the bind address either as an IP number
       string or as a hostname. In the following example we bind the http
       server to the loopback device. In other words the http server will only
       be reachable from localhost:

         set httpd port 2812 and use the address 127.0.0.1

       or

         set httpd port 2812 and use the address localhost

       If you do not use the ADDRESS statement the http server will accept
       connections on any/all local addresses.

       It is possible to hide monit's httpd server version, which usually is
       available in httpd header responses and in error pages.

         set httpd port 2812
           ...
           signature {enable|disable}

       Use disable to hide the server signature - monit will only report its
       name (e.g. 'monit' instead of for example 'monit 4.2'). By default the
       version signature is enabled. It is worth to stress that this option
       provides no security advantage and falls into the "security through
       obscurity" category.

       If you remove the httpd statement from the config file, monit will stop
       the httpd server on configuration reload. Likewise if you change the
       port number, monit will restart the http server using the new specified
       port number.

       The status page displayed by the monit web server is automatically
       refreshed with the same poll time set for the monit daemon.

       Note:

       We strongly recommend that you start monit with http support (and bind
       the server to localhost, only, unless you are behind a firewall). The
       built-in web-server is small and does not use much resources, and more
       importantly, monit can use the http server for interprocess
       communication between a monit client and a monit daemon.

       For instance, you must start a monit daemon with http support if you
       want to be able to use most of the available console commands. I.e.
       'monit stop all', 'monit start all' etc.

       If a monit daemon is running in the background we will ask the daemon
       (via the HTTP protocol) to execute the above commands.  That is, the
       daemon is requested to start and stop the services.  This ensures that
       a daemon will not restart a service that you requested to stop and that
       (any) timeout lock will be removed from a service when you start it.

       Monit HTTPD Authentication

       monit supports two types of authentication schema's for connecting to
       the httpd server, (three, if you count SSL client certificate
       validation). Both schema's can be used together or by itself. You must
       choose at least one.

       Host and network allow list

       The http server maintains an access-control list of hosts and networks
       allowed to connect to the server. You can add as many hosts as you want
       to, but only hosts with a valid domain name or its IP address are
       allowed. Networks require a network IP and a netmask to be accepted.

       The http server will query a name server to check any hosts connecting
       to the server. If a host (client) is trying to connect to the server,
       but cannot be found in the access list or cannot be resolved, the
       server will shutdown the connection to the client promptly.

       Control file example:

         set httpd port 2812
             allow localhost
             allow my.other.work.machine.com
             allow 10.1.1.1
             allow 192.168.1.0/255.255.255.0
             allow 10.0.0.0/8

       Clients, not mentioned in the allow list, trying to connect to the
       server are logged with their ip-address.

       Basic Authentication

       This authentication schema is HTTP specific and described in more
       detail in RFC 2617.

       In short; a server challenge a client (e.g. a Browser) to send
       authentication information (username and password) and if accepted, the
       server will allow the client access to the requested document.

       The biggest weakness with Basic Authentication is that the username and
       password is sent in clear-text (i.e. base64 encoded) over the network.
       It is therefor recommended that you do not use this authentication
       method unless you run the monit http server with ssl support. With ssl
       support it is completely safe to use Basic Authentication since all
       http data, including Basic Authentication headers will be encrypted.

       monit will use Basic Authentication if an allow statement contains a
       username and a password separated with a single ':' character, like so;
       allow username:password. The username and password must be written in
       clear-text.

       Alternatively you can use files in "htpasswd" format (one user:passwd
       entry per line), like so: allow [cleartext|crypt|md5] /path [users]. By
       default cleartext passwords are read. In case the passwords are
       digested it is necessary to specify the cryptographic method. If you do
       not want all users in the password file to have access to monit you can
       specify only those users that should have access, in the allow
       statement. Otherwise all users are added.

       Example1:

         set httpd port 2812
             allow hauk:password
             allow md5 /etc/httpd/htpasswd john paul ringo george

       If you use this method together with a host list, then only clients
       from the listed hosts will be allowed to connect to the monit http
       server and each client will be asked to provide a username and a
       password.

       Example2:

         set httpd port 2812
             allow localhost
             allow 10.1.1.1
             allow hauk:password

       If you only want to use Basic Authentication, then just provide allow
       entries with username and password or password files as in example 1
       above.

       Finally it is possible to define some users as read-only. A read-only
       user can read the monit web pages but will not get access to push-
       buttons and cannot change a service from the web interface.

         set httpd port 2812
             allow admin:password
             allow hauk:password read-only

       A user is set to read-only by using the read-only keyword after
       username:password. In the above example the user hauk is defined as a
       read-only user, while the admin user has all access rights.

       NB! a monit client will use the first username:password pair in an
       allow list and you should not define the first user as a read-only
       user. If you do, monit console commands will not work.

       If you use Basic Authentication it is a good idea to set the access
       permission for the control file (~/.monitrc) to only readable and
       writable for the user running monit, because the password is written in
       clear-text. (Use this command, /bin/chmod 600 ~/.monitrc). In fact,
       since monit version 3.0, monit will complain and exit if the control
       file is readable by others.

       Clients trying to connect to the server but supply the wrong username
       and/or password are logged with their ip-address.

       If the monit command line interface is being used, at least one
       cleartext password is necessary. Otherwise, the monit command line
       interface will not be able to connect to the monit daemon server.

DEPENDENCIES
       If specified in the control file, monit can do dependency checking
       before start, stop, monitoring or unmonitoring of services. The
       dependency statement may be used within any service entries in the
       monit control file.

       The syntax for the depend statement is simply:

       DEPENDS on service[, service [,...]]

       Where service is a service entry name, for instance apache or datafs.

       You may add more than one service name of any type or use more than one
       depend statement in an entry.

       Services specified in a depend statement will be checked during
       stop/start/monitor/unmonitor operations. If a service is stopped or
       unmonitored it will stop/unmonitor any services that depends on itself.
       Likewise, if a service is started, it will first stop any services that
       depends on itself and after it is started, start all depending services
       again. If the service is to be monitored (enable monitoring), all
       services which this service depends on will be monitored before
       enabling monitoring of this service.

       Here is an example where we set up an apache service entry to depend on
       the underlying apache binary. If the binary should change an alert is
       sent and apache is not monitored anymore. The rationale is security and
       that monit should not execute a possibly cracked apache binary.

        (1) check process apache
        (2)    with pidfile "/usr/local/apache/logs/httpd.pid"
        (3)    ...
        (4)    depends on httpd
        (5)
        (6) check file httpd with path /usr/local/apache/bin/httpd
        (7)    if failed checksum then unmonitor

       The first entry is the process entry for apache shown before
       (abbreviated for clarity). The fourth line sets up a dependency between
       this entry and the service entry named httpd in line 6. A depend tree
       works as follows, if an action is conducted in a lower branch it will
       propagate upward in the tree and for every dependent entry execute the
       same action. In this case, if the checksum should fail in line 7 then
       an unmonitor action is executed and the apache binary is not checked
       anymore. But since the apache process entry depends on the httpd entry
       this entry will also execute the unmonitor action. In short, if the
       checksum test for the httpd binary file should fail, both the check
       file httpd entry and the check process apache entry is set in un-
       monitoring mode.

       A dependency tree is a general construct and can be used between all
       types of service entries and span many levels and propagate any
       supported action (except the exec action which will not propagate
       upward in a dependency tree for obvious reasons).

       Here is another different example. Consider the following common server
       setup:

         WEB-SERVER -> APPLICATION-SERVER -> DATABASE -> FILESYSTEM
             (a)               (b)             (c)          (d)

       You can set dependencies so that the web-server depends on the
       application server to run before the web-server starts and the
       application server depends on the database server and the database
       depends on the file-system to be mounted before it starts. See also the
       example section below for examples using the depend statement.

       Here we describe how monit will function with the above dependencies:

       If no servers are running
           monit will start the servers in the following order: d, c, b, a

       If all servers are running
           When you run 'monit stop all' this is the stop order: a, b, c, d.
           If you run 'monit stop d' then a, b and c are also stopped because
           they depend on d and finally d is stopped.

       If a does not run
           When monit runs it will start a

       If b does not run
           When monit runs it will first stop a then start b and finally start
           a again.

       If c does not run
           When monit runs it will first stop a and b then start c and finally
           start b then a.

       If d does not run
           When monit runs it will first stop a, b and c then start d and
           finally start c, b then a.

       If the control file contains a depend loop.
           A depend loop is for example; a->b and b->a or a->b->c->a.

           When monit starts it will check for such loops and complain and
           exit if a loop was found. It will also exit with a complaint if a
           depend statement was used that does not point to a service in the
           control file.

THE RUN CONTROL FILE
       The preferred way to set up monit is to write a .monitrc file in your
       home directory. When there is a conflict between the command-line
       arguments and the arguments in this file, the command-line arguments
       take precedence. To protect the security of your control file and
       passwords the control file must have permissions no more than 0700
       (u=xrw,g=,o=); monit will complain and exit otherwise.

       Run Control Syntax

       Comments begin with a '#' and extend through the end of the line.
       Otherwise the file consists of a series of service entries or global
       option statements in a free-format, token-oriented syntax.

       There are three kinds of tokens: grammar keywords, numbers (i.e.
       decimal digit sequences) and strings. Strings can be either quoted or
       unquoted. A quoted string is bounded by double quotes and may contain
       whitespace (and quoted digits are treated as a string). An unquoted
       string is any whitespace-delimited token, containing characters and/or
       numbers.

       On a semantic level, the control file consists of two types of entries:

       1. Global set-statements
           A global set-statement starts with the keyword set and the item to
           configure.

       2. One or more service entry statements.
           Each service entry consists of the keywords `check', followed by
           the service type. Each entry requires a <unique> descriptive name,
           which may be freely chosen. This name is used by monit to refer to
           the service internally and in all interactions with the user.

       Currently, six types of check statements are supported:

       1. CHECK PROCESS <unique name> PIDFILE <path>
           <path> is the absolute path to the program's pidfile. If the
           pidfile does not exist or does not contain the pid number of a
           running process, monit will call the entry's start method if
           defined, If monit runs in passive mode or the start methods is not
           defined, monit will just send alerts on errors.

       2. CHECK FILE <unique name> PATH <path>
           <path> is the absolute path to the file. If the file does not exist
           or disappeared, monit will call the entry's start method if
           defined, if <path> does not point to a regular file type (for
           instance a directory), monit will disable monitoring of this entry.
           If monit runs in passive mode or the start methods is not defined,
           monit will just send alerts on errors.

       3. CHECK FIFO <unique name> PATH <path>
           <path> is the absolute path to the fifo. If the fifo does not exist
           or disappeared, monit will call the entry's start method if
           defined, if <path> does not point to a fifo type (for instance a
           directory), monit will disable monitoring of this entry. If monit
           runs in passive mode or the start methods is not defined, monit
           will just send alerts on errors.

       4. CHECK DEVICE <unique name> PATH <path>
           <path> is the path to the device block special file, mount point,
           file or a directory which is part of a filesystem. It is
           recommended to use a block special file directly (for example
           /dev/hda1 on Linux or /dev/dsk/c0t0d0s1 on Solaris, etc.) If you
           use a mount point (for example /data), be careful, because if the
           device is unmounted the test will still be true because the mount
           point exist.

           If the device becomes unavailable, monit will call the entry's
           start method if defined. if <path> does not point to a device,
           monit will disable monitoring of this entry. If monit runs in
           passive mode or the start methods is not defined, monit will just
           send alerts on errors.

       5. CHECK DIRECTORY <unique name> PATH <path>
           <path> is the absolute path to the directory. If the directory does
           not exist or disappeared, monit will call the entry's start method
           if defined, if <path> does not point to a directory, monit will
           disable monitoring of this entry. If monit runs in passive mode or
           the start methods is not defined, monit will just send alerts on
           errors.

       6. CHECK HOST <unique name> ADDRESS <host address>
           The host address can be specified as a hostname string or as an ip-
           address string on a dotted decimal format. Such as, tildeslash.com
           or "64.87.72.95".

       7. CHECK SYSTEM <unique name>
           The system name is usualy hostname, but any descriptive name can be
           used. This test allows to check general system resources such as
           CPU usage (percent of time spent in user, system and wait), total
           memory usage or load average.

       You can use noise keywords like 'if', `and', `with(in)', `has',
       `using', 'use', 'on(ly)', `usage' and `program(s)' anywhere in an entry
       to make it resemble English. They're ignored, but can make entries much
       easier to read at a glance. The punctuation characters ';' ',' and '='
       are also ignored. Keywords are case insensitive.

        Here are the legal global keywords:

        Keyword         Function
        ----------------------------------------------------------------
        set daemon      Set a background poll interval in seconds.
        set init        Set monit to run from init. monit will not
                        transform itself into a daemon process.
        set logfile     Name of a file to dump error- and status-
                        messages to. If syslog is specified as the
                        file, monit will utilize the syslog daemon
                        to log messages. This can optionally be
                        followed by 'facility <facility>' where
                        facility is 'log_local0' - 'log_local7' or
                        'log_daemon'. If no facility is specified,
                        LOG_USER is used.
        set mailserver  The mailserver used for sending alert
                        notifications. If the mailserver is not
                        defined, monit will try to use 'localhost'
                        as the smtp-server for sending mail. You
                        can add more mail servers, if monit cannot
                        connect to the first server it will try the
                        next server and so on.
        set mail-format Set a global mail format for all alert
                        messages emitted by monit.
        set pidfile     Explicit set the location of the monit lock
                        file. E.g. set pidfile /var/run/xyzmonit.pid.
        set statefile   Explicit set the location of the file monit
                        will write state data to. If not set, the
                        default is $HOME/.monit.state.
        set httpd port  Activates monit http server at the given
                        port number.
        ssl enable      Enables ssl support for the httpd server.
                        Requires the use of the pemfile statement.
        ssl disable     Disables ssl support for the httpd server.
                        It is equal to omitting any ssl statement.
        pemfile         Set the pemfile to be used with ssl.
        clientpemfile   Set the pemfile to be used when client
                        certificates should be checked by monit.
        address         If specified, the http server will only
                        accept connect requests to this addresses
                        This statement is an optional part of the
                        set httpd statement.
        allow           Specifies a host or IP address allowed to
                        connect to the http server. Can also specify
                        a username and password allowed to connect
                        to the server. More than one allow statement
                        are allowed. This statement is also an
                        optional part of the set httpd statement.
        read-only       Set the user defined in username:password
                        to read only. A read-only user cannot change
                        a service from the monit web interface.
        include         include a file or files matching the globstring

        Here are the legal service entry keywords:

        Keyword         Function
        ----------------------------------------------------------------
        check           Starts an entry and must be followed by the type
                        of monitored service {device|directory|file|host
                        process|system} and a descriptive name for the
                        service.
        pidfile         Specify the  process pidfile. Every
                        process must create a pidfile with its
                        current process id. This statement should only
                        be used in a process service entry.
        path            Must be followed by a path to the block
                        special file for filesystem (device), regular
                        file, directory or a process's pidfile.
        group           Specify a groupname for a service entry.
        start           The program used to start the specified
                        service. Full path is required. This
                        statement is optional, but recommended.
        stop            The program used to stop the specified
                        service. Full path is required. This
                        statement is optional, but recommended.
        pid and ppid    These keywords may be used as standalone
                        statements in a process service entry to
                        override the alert action for change of
                        process pid and ppid.
        uid and gid     These keywords are either 1) an optional part of
                        a start, stop or exec statement. They may be
                        used to specify a user id and a group id the
                        program (process) should switch to upon start.
                        This feature can only be used if the superuser
                        is running monit. 2) uid and gid may also be
                        used as standalone statements in a file service
                        entry to test a file's uid and gid attributes.
        host            The hostname or IP address to test the port
                        at. This keyword can only be used together
                        with a port statement or in the check host
                        statement.
        port            Specify a TCP/IP service port number which
                        a process is listening on. This statement
                        is also optional. If this statement is not
                        prefixed with a host-statement, localhost is
                        used as the hostname to test the port at.
        type            Specifies the socket type monit should use when
                        testing a connection to a port. If the type
                        keyword is omitted, tcp is used. This keyword
                        must be followed by either tcp, udp or tcpssl.
        tcp             Specifies that monit should use a TCP
                        socket type (stream) when testing a port.
        tcpssl          Specifies that monit should use a TCP socket
                        type (stream) and the secure socket layer (ssl)
                        when testing a port connection.
        udp             Specifies that monit should use a UDP socket
                        type (datagram) when testing a port.
        certmd5         The md5 sum of a certificate a ssl forged
                        server has to deliver.
        proto(col)      This keyword specifies the type of service
                        found at the port. monit knows at the moment
                        how to speak HTTP, SMTP, FTP, POP, IMAP, MYSQL,
                        NNTP, SSH, DWP, LDAP2, LDAP3, RDATE, NTP3, DNS,
                        POSTFIX-POLICY, APACHE-STATUS, TNS, PGSQL and
                        RSYNC.
                        You're welcome to write new protocol test
                        modules. If no protocol is specified monit will
                        use a default test which in most cases are good
                        enough.
        request         Specifies a server request and must come
                        after the protocol keyword mentioned above.
                         - for http it can contain an URL and an
                           optional query string.
                         - other protocols does not support this
                           statement yet
        send/expect     These keywords specify a generic protocol.
                        Both require a string whether to be sent or
                        to be matched against (as extended regex if
                        supported).  Send/expect can not be used
                        together with the proto(col) statement.
        unix(socket)    Specifies a Unix socket file and used like
                        the port statement above to test a Unix
                        domain network socket connection.
        URL             Specify an URL string which monit will use for
                        connection testing.
        content         Optional sub-statement for the URL statement.
                        Specifies that monit should test the content
                        returned by the server against a regular
                        expression.
        timeout x sec.  Define a network port connection timeout. Must
                        be followed by a number in seconds and the
                        keyword, seconds.
        timeout         Define a service timeout. Must be followed by
                        two digits. The first digit is max number of
                        restarts for the service. The second digit
                        is the cycle interval to test restarts.
                        This statement is optional.
        alert           Specifies an email address for notification
                        if a service event occurs. Alert can also
                        be postfixed, to only send a message for
                        certain events. See the examples above. More
                        than one alert statement is allowed in an
                        entry. This statement is also optional.
        noalert         Specifies an email address which don't want
                        to receive alerts. This statement is also
                        optional.
        restart, stop   These keywords may be used as actions for
        unmonitor,      various test statements. The exec statement is
        start and       special in that it requires a following string
        exec            specifying the program to be execute. You may
                        also specify an UID and GID for the exec
                        statement. The program executed will then run
                        using the specified user id and group id.
        mail-format     Specifies a mail format for an alert message
                        This statement is an optional part of the
                        alert statement.
        checksum        Specify that monit should compute and monitor a
                        file's md5/sha1 checksum. May only be used in a
                        check file entry.
        expect          Specifies a md5/sha1 checksum string monit
                        should expect when testing the checksum. This
                        statement is an optional part of the checksum
                        statement.
        timestamp       Specifies an expected timestamp for a file
                        or directory. More than one timestamp statement
                        are allowed. May only be used in a check file or
                        check directory entry.
        changed         Part of a timestamp statement and used as an
                        operator to simply test for a timestamp change.
        every           Validate this entry only at every n poll cycle.
                        Useful in daemon mode when the cycle is short
                        and a service takes some time to start.
        mode            Must be followed either by the keyword active,
                        passive or manual. If active, monit will restart
                        the service if it is not running (this is the
                        default behavior). If passive, monit will not
                        (re)start the service if it is not running - it
                        will only monitor and send alerts (resource
                        related restart and stop options are ignored
                        in this mode also). If manual, monit will enter
                        active mode only if a service was started under
                        monit's control otherwise the service isn't
                        monitored.
        cpu             Must be followed by a compare operator, a number
                        with "%" and an action. This statement is used
                        to check the cpu usage in percent of a process
                        with its children over a number of cycles. If
                        the compare expression matches then the
                        specified action is executed.
        mem             The equivalent to the cpu token for memory of a
                        process (w/o children!).  This token must be
                        followed by a compare operator a number with
                        unit {B|KB|MB|GB|%|byte|kilobyte|megabyte|
                        gigabyte|percent} and an action.
        loadavg         Must be followed by [1min,5min,15min] in (), a
                        compare operator, a number and an action. This
                        statement is used to check the system load
                        average over a number of cycles. If the compare
                        expression matches then the specified action is
                        executed.
        children        This is the number of child processes spawn by a
                        process. The syntax is the same as above.
        totalmem        The equivalent of mem, except totalmem is an
                        aggregation of memory, not only used by a
                        process but also by all its child
                        processes. The syntax is the same as above.
        space           Must be followed by a compare operator, a
                        number, unit {B|KB|MB|GB|%|byte|kilobyte|
                        megabyte|gigabyte|percent} and an action.
        inode(s)        Must be followed by a compare operator, integer
                        number, optionally by percent sign (if not, the
                        limit is absolute) and an action.
        perm(ission)    Must be followed by an octal number describing
                        the permissions.
        size            Must be followed by a compare operator, a
                        number, unit {B|KB|MB|GB|byte|kilobyte|
                        megabyte|gigabyte} and an action.
        depends (on)    Must be followed by the name of a service this
                        service depends on.

       Here's the complete list of reserved keywords used by monit:

       if, then, else, set, daemon, logfile, syslog, address, httpd, ssl,
       enable, disable, pemfile, allow, read-only, check, init, count,
       pidfile, statefile, group, start, stop, uid, gid, connection,
       port(number), unix(socket), type, proto(col), tcp, tcpssl, udp, alert,
       noalert, mail-format, restart, timeout, checksum, resource, expect,
       send, mailserver, every, mode, active, passive, manual, depends, host,
       default, http, ftp, smtp, pop, ntp3, nntp, imap, clamav, ssh, dwp,
       ldap2, ldap3, tns, request, cpu, mem, totalmem, children, loadavg,
       timestamp, changed, second(s), minute(s), hour(s), day(s), space,
       inode, pid, ppid, perm(ission), icmp, process, file, directory, device,
       size, unmonitor, rdate, rsync, data, invalid, exec, nonexist, policy,
       reminder, instance, eventqueue,
        basedir, slot(s), system and failed

       And here is a complete list of noise keywords ignored by monit:

       is, as, are, on(ly), with(in), and, has, using, use, the, sum,
       program(s), than, for, usage, was, but, of.

       Note: If the start or stop programs are shell scripts, then the script
       must begin with "#!" and the remainder of the first line must specify
       an interpreter for the program. E.g.  "#!/bin/sh"

       It's possible to write scripts directly into the start and stop entries
       by using a string of shell-commands. Like so:

        start="/bin/bash -c 'echo $$ > pidfile; exec program'"
        stop="/bin/bash -c 'kill -s SIGTERM `cat pidfile`'"

       CONFIGURATION EXAMPLES

       The simplest form is just the check statement. In this example we check
       to see if the server is running and log a message if not:

        check process resin with pidfile /usr/local/resin/srun.pid

       To have monit start the server if it's not running, add a start
       statement:

        check process resin with pidfile /usr/local/resin/srun.pid
              start program = "/usr/local/resin/bin/srun.sh start"

       Here's a more advanced example for monitoring an apache web-server
       listening on the default port number for HTTP and HTTPS. In this
       example monit will restart apache if it's not accepting connections at
       the port numbers. The method monit use for a process restart is to
       first execute the stop-program, wait for the process to stop and then
       execute the start-program. (If monit was unable to stop or start the
       service a failed alert message will be sent if you have requested alert
       messages to be sent).

        check process apache with pidfile /var/run/httpd.pid
              start program = "/etc/init.d/httpd start"
              stop program  = "/etc/init.d/httpd stop"
              if failed port 80 then restart
              if failed port 443 with timeout 15 seconds then restart

       This example demonstrate how you can run a program as a specified user
       (uid) and with a specified group (gid). Many daemon programs will do
       the uid and gid switch by them self, but for those programs that does
       not (e.g. Java programs), monit's ability to start a program as a
       certain user can be very useful. In this example we start the Tomcat
       Java Servlet Engine as the standard nobody user and group. Please note
       that monit will only switch uid and gid for a program if the super-user
       is running monit, otherwise monit will simply ignore the request to
       change uid and gid.

        check process tomcat with pidfile /var/run/tomcat.pid
              start program = "/etc/init.d/tomcat start"
                    as uid nobody and gid nobody
              stop program  = "/etc/init.d/tomcat stop"
                    # You can also use id numbers instead and write:
                    as uid 99 and with gid 99
              if failed port 8080 then alert

       In this example we use udp for connection testing to check if the name-
       server is running and also use timeout and alert:

        check process named with pidfile /var/run/named.pid
              start program = "/etc/init.d/named start"
              stop program  = "/etc/init.d/named stop"
              if failed port 53 use type udp protocol dns then restart
              if 3 restarts within 5 cycles then timeout

       The following example illustrate how to check if the service 'sophie'
       is answering connections on its Unix domain socket:

        check process sophie with pidfile /var/run/sophie.pid
              start program = "/etc/init.d/sophie start"
              stop  program = "/etc/init.d/sophie stop"
              if failed unix /var/run/sophie then restart

       In this example we check an apache web-server running on localhost that
       answers for several IP-based virtual hosts or vhosts, hence the host
       statement before port:

        check process apache with pidfile /var/run/httpd.pid
              start "/etc/init.d/httpd start"
              stop  "/etc/init.d/httpd stop"
              if failed host www.sol.no port 80 then alert
              if failed host shop.sol.no port 443 then alert
              if failed host chat.sol.no port 80 then alert
              if failed host www.tildeslash.com port 80 then alert

       To make sure that monit is communicating with a http server a protocol
       test can be added:

        check process apache with pidfile /var/run/httpd.pid
              start "/etc/init.d/httpd start"
              stop  "/etc/init.d/httpd stop"
              if failed host www.sol.no port 80
                 protocol HTTP
                 then alert

       This example shows a different way to check a webserver using the
       send/expect mechanism:

        check process apache with pidfile /var/run/httpd.pid
              start "/etc/init.d/httpd start"
              stop  "/etc/init.d/httpd stop"
              if failed host www.sol.no port 80
                 send "GET / HTTP/1.0\r\nHost: www.sol.no\r\n\r\n"
                 expect "HTTP/[0-9\.]{3} 200 .*\r\n"
                 then alert

       To make sure that Apache is logging successfully (i.e. no more than 60
       percent of child servers are logging), use its mod_status page at
       www.sol.no/server-status with this special protocol test:

        check process apache with pidfile /var/run/httpd.pid
              start "/etc/init.d/httpd start"
              stop  "/etc/init.d/httpd stop"
              if failed host www.sol.no port 80
              protocol apache-status loglimit > 60% then restart

       This configuration can be used to alert you if 25 percent or more of
       Apache child processes are stuck performing DNS lookups:

        check process apache with pidfile /var/run/httpd.pid
              start "/etc/init.d/httpd start"
              stop  "/etc/init.d/httpd stop"
              if failed host www.sol.no port 80
              protocol apache-status dnslimit > 25% then alert

       Here we use an icmp ping test to check if a remote host is up and if
       not send an alert:

        check host www.tildeslash.com with address www.tildeslash.com
              if failed icmp type echo count 5 with timeout 15 seconds
                 then alert

       In the following example we ask monit to compute and verify the
       checksum for the underlying apache binary used by the start and stop
       programs. If the the checksum test should fail, monitoring will be
       disabled to prevent possibly starting a compromised binary:

        check process apache with pidfile /var/run/httpd.pid
              start program = "/etc/init.d/httpd start"
              stop program  = "/etc/init.d/httpd stop"
              if failed host www.tildeslash.com port 80 then restart
              depends on apache_bin

        check file apache_bin with path /usr/local/apache/bin/httpd
              if failed checksum then unmonitor

       In this example we ask monit to test the checksum for a document on a
       remote server. If the checksum was changed we send an alert:

        check host tildeslash with address www.tildeslash.com
              if failed port 80 protocol http
                 and request "/monit/dist/monit-4.0.tar.gz"
                     with checksum f9d26b8393736b5dfad837bb13780786
              then alert
              alert hauk@tildeslash.com with mail-format {subject:
                Aaaalarm! }

       Some servers are slow starters, like for example Java based Application
       Servers. So if we want to keep the poll-cycle low (i.e. < 60 seconds)
       but allow some services to take its time to start, the every statement
       is handy:

        check process dynamo with pidfile /etc/dynamo.pid
              start program = "/etc/init.d/dynamo start"
              stop program  = "/etc/init.d/dynamo stop"
              if failed port 8840 then alert
              every 2 cycles

       Here is an example where we group together two database entries so you
       can manage them together, e.g.; 'monit -g database start all'. The mode
       statement is also illustrated in the first entry and have the effect
       that monit will not try to (re)start this service if it is not running:

        check process sybase with pidfile /var/run/sybase.pid
              start = "/etc/init.d/sybase start"
              stop  = "/etc/init.d/sybase stop"
              mode passive
              group database

        check process oracle with pidfile /var/run/oracle.pid
              start program = "/etc/init.d/oracle start"
              stop program  = "/etc/init.d/oracle stop"
              mode active # Not necessary really, since it's the default
              if failed port 9001 then restart
              group database

       Here is an example to show the usage of the resource checks. It will
       send an alert when the CPU usage of the http daemon and its child
       processes raises beyond 60% for over two cycles. Apache is restarted if
       the CPU usage is over 80% for five cycles or the memory usage over
       100Mb for five cycles or if the machines load average is more than 10
       for 8 cycles:

        check process apache with pidfile /var/run/httpd.pid
              start program = "/etc/init.d/httpd start"
              stop program  = "/etc/init.d/httpd stop"
              if cpu > 60% for 2 cycles then alert
              if cpu > 80% for 5 cycles then restart
              if mem > 100 MB for 5 cycles then stop
              if loadavg(5min) greater than 10.0 for 8 cycles then stop

       This examples demonstrate the timestamp statement with exec and how you
       may restart apache if its configuration file was changed.

        check file httpd.conf with path /etc/httpd/httpd.conf
              if changed timestamp
                 then exec "/etc/init.d/httpd graceful"

       In this example we demonstrate usage of the extended alert statement
       and a file check dependency:

        check process apache with pidfile /var/run/httpd.pid
             start = "/etc/init.d/httpd start"
             stop  = "/etc/init.d/httpd stop"
             if failed host www.tildeslash.com  port 80 then restart
             alert admin@bar on {nonexist, timeout}
               with mail-format {
                     from:     bofh@$HOST
                     subject:  apache $EVENT - $ACTION
                     message:  This event occurred on $HOST at $DATE.
                     Your faithful employee,
                     monit
             }
             if 3 restarts within 5 cycles then timeout
             depend httpd_bin
             group apache

        check file httpd_bin with path /usr/local/apache/bin/httpd
              if failed checksum
                 and expect 8f7f419955cefa0b33a2ba316cba3659
                     then unmonitor
              if failed permission 755 then unmonitor
              if failed uid root then unmonitor
              if failed gid root then unmonitor
              if changed timestamp then alert
              alert security@bar on {checksum, timestamp,
                                     permission, uid, gid}
                    with mail-format {subject: Alaaarrm! on $HOST}
              group apache

       In this example, we demonstrate usage of the depend statement. In this
       case, we want to start oracle and apache. However, we've set up apache
       to use oracle as a back end, and if oracle is restarted, apache must be
       restarted as well.

        check process apache with pidfile /var/run/httpd.pid
              start = "/etc/init.d/httpd start"
              stop  = "/etc/init.d/httpd stop"
              depends on oracle

        check process oracle with pidfile /var/run/oracle.pid
              start = "/etc/init.d/oracle start"
              stop  = "/etc/init.d/oracle stop"
              if failed port 9001 then restart

       Next, we have 2 services, oracle-import and oracle-export that need to
       be restarted if oracle is restarted, but are independent of each other.

        check process oracle with pidfile /var/run/oracle.pid
              start = "/etc/init.d/oracle start"
              stop  = "/etc/init.d/oracle stop"
              if failed port 9001 then restart

        check process oracle-import
             with pidfile /var/run/oracle-import.pid
              start = "/etc/init.d/oracle-import start"
              stop  = "/etc/init.d/oracle-import stop"
              depends on oracle

        check process oracle-export
             with pidfile /var/run/oracle-export.pid
              start = "/etc/init.d/oracle-export start"
              stop  = "/etc/init.d/oracle-export stop"
              depends on oracle

       Finally an example with all statements:

        check process apache with pidfile /var/run/httpd.pid
              start program = "/etc/init.d/httpd start"
              stop program  = "/etc/init.d/httpd stop"
              if 3 restarts within 5 cycles then timeout
              if failed host www.sol.no  port 80 protocol http
                 and use the request "/login.cgi"
                     then alert
              if failed host shop.sol.no port 443 type tcpssl
                 protocol http and with timeout 15 seconds
                     then restart
              if cpu is greater than 60% for 2 cycles then alert
              if cpu > 80% for 5 cycles then restart
              if totalmem > 100 MB then stop
              if children > 200 then alert
              alert bofh@bar with mail-format {from: monit@foo.bar.no}
              every 2 cycles
              mode active
              depends on weblogic
              depends on httpd.pid
              depends on httpd.conf
              depends on httpd_bin
              depends on datafs
              group server

        check file httpd.pid with path /usr/local/apache/logs/httpd.pid
              group server
              if timestamp > 7 days then restart
              every 2 cycles
              alert bofh@bar with mail-format {from: monit@foo.bar.no}
              depends on datafs

        check file httpd.conf with path /etc/httpd/httpd.conf
              group server
              if timestamp was changed
                 then exec "/usr/local/apache/bin/apachectl graceful"
              every 2 cycles
              alert bofh@bar with mail-format {from: monit@foo.bar.no}
              depends on datafs

        check file httpd_bin with path /usr/local/apache/bin/httpd
              group server
              if failed checksum and expect the sum
                 8f7f419955cefa0b33a2ba316cba3659 then unmonitor
              if failed permission 755 then unmonitor
              if failed uid root then unmonitor
              if failed gid root then unmonitor
              if changed size then alert
              if changed timestamp then alert
              every 2 cycles
              alert bofh@bar with mail-format {from: monit@foo.bar.no}
              alert foo@bar on { checksum, size, timestamp, uid, gid }
              depends on datafs

        check device datafs with path /dev/sdb1
              group server
              start program  = "/bin/mount /data"
              stop program  =  "/bin/umount /data"
              if failed permission 660 then unmonitor
              if failed uid root then unmonitor
              if failed gid disk then unmonitor
              if space usage > 80 % then alert
              if space usage > 94 % then stop
              if inode usage > 80 % then alert
              if inode usage > 94 % then stop
              alert root@localhost

        check host ftp.redhat.com with address ftp.redhat.com
              if failed icmp type echo with timeout 15 seconds
                 then alert
              if failed port 21 protocol ftp
                 then exec "/usr/X11R6/bin/xmessage -display
                            :0 ftp connection failed"
              alert foo@bar.com

        check host www.gnu.org with address www.gnu.org
              if failed port 80 protocol http
                 and request "/pub/gnu/bash/bash-2.05b.tar.gz"
                     with checksum 8f7f419955cefa0b33a2ba316cba3659
              then alert
              alert rms@gnu.org with mail-format {
                   subject: The gnu server may be hacked again! }

       Note; only the check type, pidfile/path/address statements are
       mandatory, the other statements are optional and the order of the
       optional statements is not important.

MONIT WITH HEARTBEAT
       You can download heartbeat from http://www.linux-ha.org/download/. It
       might be useful to have a look at The Heartbeat Getting Started Guide
       at: http://www.linux-ha.org/GettingStarted.html

       Starting up a Node

       This is the normal start sequence for a cluster-node. With this
       sequence, there should be no error-case, which is not handled either by
       heartbeat or by monit. For example, if monit dies, initd restarts it.
       If heartbeat dies, monit restarts it. If the node dies, the heartbeat
       instance on the other node detects it and restart the services there.

       1. initd starts monit with group local
       2. monit starts heartbeat in local group
       3. heartbeat requests monit to start the node group
       4. monit starts the node group

       Monit: /etc/monitrc

       This example describes a cluster with 2 nodes. Services running on Node
       1 are in the group node1 and Node 2 services are in the node2 group.

       The local group entries are mode active, the node group entries are
       mode manual and controlled by heartbeat.

        #
        # local services on both hosts
        #

        check process heartbeat with pidfile /var/run/heartbeat.pid
              start program = "/etc/init.d/heartbeat start"
              stop  program = "/etc/init.d/heartbeat start"
              mode  active
              alert foo@bar
              group local

        check process postfix with pidfile /var/run/postfix/master.pid
              start program = "/etc/init.d/postfix start"
              stop program  = "/etc/init.d/postfix stop"
              mode  active
              alert foo@bar
              group local

        #
        # node1 services
        #

        check process apache with pidfile /var/apache/logs/httpd.pid
              start program = "/etc/init.d/apache start"
              stop program  = "/etc/init.d/apache stop"
              depends named
              alert foo@bar
              mode  manual
              group node1

        check process named with pidfile /var/tmp/named.pid
              start program = "/etc/init.d/named start"
              stop program  = "/etc/init.d/named stop"
              alert foo@bar
              mode  manual
              group node1

        #
        # node2 services
        #

        check process named-slave with pidfile /var/tmp/named-slave.pid
              start program = "/etc/init.d/named-slave start"
              stop program  = "/etc/init.d/named-slave stop"
              mode  manual
              alert foo@bar
              group node2

        check process squid with pidfile /var/squid/logs/squid.pid
              start program = "/etc/init.d/squid start"
              stop program  = "/etc/init.d/squid stop"
              depends named-slave
              alert foo@bar
              mode  manual
              group node2

       initd:  /etc/inittab

       Monit is started on both nodes with initd. You will need to add an
       entry in /etc/inittab to start monit with the same local group
       heartbeat is member of.

        #/etc/inittab
        mo:2345:respawn:/usr/local/bin/monit -d 10 -c /etc/monitrc -g local

       heartbeat:  /etc/ha.d/haresources

       When heartbeat starts, heartbeat looks up the node entry and start the
       script /etc/init.d/monit-node1 or /etc/init.d/monit-node2. The script
       calls monit to start the specific group per node.

        # /etc/ha.d/haresources
        node1 IPaddr::172.16.100.1  monit-node1
        node2 IPaddr::172.16.100.2  monit-node2

       /etc/init.d/monit-node1

        #!/bin/bash
        #
        # sample script for starting/stopping all services on node1
        #
        prog="/usr/local/bin/monit -g node1"
        start()
        {
              echo -n $"Starting $prog:"
              $prog start all
              echo
        }

        stop()
        {
              echo -n $"Stopping $prog:"
              $prog stop all
              echo
        }

        case "$1" in
              start)
                   start;;
              stop)
                   stop;;
              *)
                   echo $"Usage: $0 {start|stop}"
                   RETVAL=1
        esac
        exit $RETVAL

       Handling state

       As mentioned elsewhere, monit save its state to a state file. If the
       monit process should die, upon restart monit will read its last known
       state from this file. This can be a problem if monit is used in a
       cluster, as illustrate in this scenario:

       1   The active node fails, the second takes over

       2   After a reboot, the failed node comes back, monit read its state
           file and start all the services (even manual ones) as they were
           running before the failure. This is a problem because services will
           now run on both nodes.

       The solution to this problem is to remove the monit.state file in a rc-
       script called at boot time and before monit is started.

FILES
       ~/.monitrc
          Default run control file

       /etc/monitrc
          If the control file is not found in the default
          location and /etc contains a monitrc file, this
          file will be used instead.

       ./monitrc
          If the control file is not found in either of the
          previous two locations, and the current working
          directory contains a monitrc file, this file is
          used instead.

       ~/.monitrc.pid
          Lock file to help prevent concurrent runs (non-root
          mode).

       /var/run/monit.pid
          Lock file to help prevent concurrent runs (root mode,
          Linux systems).

       /etc/monit.pid
          Lock file to help prevent concurrent runs (root mode,
          systems without /var/run).

       ~/.monit.state
          monit save its state to this file and utilize
          information found in this file to recover from
          a crash. This is a binary file and its content is
          only of interest to monit. You may set the location
          of this file in the monit control file or by using
          the -s switch when monit is started.

ENVIRONMENT
       No environment variables are used by monit. However, when monit execute
       a script or a program monit will set several environment variables
       which can be utilized by the executable. The following and only the
       following environment variables are available:

       MONIT_EVENT
           The event that occurred on the service

       MONIT_SERVICE
           The name of the service (from monitrc) on which the event occurred.

       MONIT_DATE
           The time and date (rfc 822 style) the event occurred

       MONIT_HOST
           The host the event occurred on

       The following environment variables are only available for process
       service entries:

       MONIT_PROCESS_PID
           The process pid. This may be 0 if the process was (re)started,

       MONIT_PROCESS_MEMORY
           Process memory. This may be 0 if the process was (re)started,

       MONIT_PROCESS_CHILDREN
           Process children. This may be 0 if the process was (re)started,

       MONIT_PROCESS_CPU_PERCENT
           Process cpu%. This may be 0 if the process was (re)started,

       In addition the following spartan PATH environment variable is
       available:

       PATH=/bin:/usr/bin:/sbin:/usr/sbin

       Scripts or programs that depends on other environment variables or on a
       more verbose PATH must provide means to set these variables by them
       self.

SIGNALS
       If a monit daemon is running, SIGUSR1 wakes it up from its sleep phase
       and forces a poll of all services. SIGTERM and SIGINT will gracefully
       terminate a monit daemon. The SIGTERM signal is sent to a monit daemon
       if monit is started with the quit action argument.

       Sending a SIGHUP signal to a running monit daemon will force the daemon
       to reinitialize itself, specifically it will reread configuration,
       close and reopen log files.

       Running monit in foreground while a background monit daemon is running
       will wake up the daemon.

NOTES
       This is a very silent program. Use the -v switch if you want to see
       what monit is doing, and tail -f the logfile. Optionally for testing
       purposes; you can start monit with the -Iv switch. Monit will then
       print debug information to the console, to stop monit in this mode,
       simply press CTRL^C (i.e. SIGINT) in the same console.

       The syntax (and parser) of the control file is inspired by Eric S.
       Raymond et al. excellent fetchmail program. Some portions of this man
       page does also receive inspiration from the same authors.

AUTHORS
       Jan-Henrik Haukeland <hauk@tildeslash.com>, Martin Pala
       <martinp@tildeslash.com>, Christian Hopp <chopp@iei.tu-clausthal.de>,
       Rory Toma <rory@digeo.com>

       See also http://www.tildeslash.com/monit/who.html

COPYRIGHT
       Copyright (C) 2000-2007 by the monit project group. All Rights
       Reserved. This product is distributed in the hope that it will be
       useful, but WITHOUT any warranty; without even the implied warranty of
       MERCHANTABILITY or FITNESS for a particular purpose.

SEE ALSO
       GNU text utilities; md5sum(1); sha1sum(1); openssl(1); glob(7);
       regex(7)



November 06. 2007             www.tildeslash.com                      MONIT(1)
