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MONITORD(8)            DragonFly System Manager's Manual           MONITORD(8)


NAME

     monitord - monitor system services for accidental termination


SYNOPSIS

     monitord [-f file -t interval]


DESCRIPTION

     monitord is a simple to use system service that allows one to easily
     monitor other system services for accidental termination. If they
     terminate because of some internal bug or illegitimate action, such as a
     DoS attack, they are restarted with the given username and parameters
     specified in monitord.conf.

     The two command line options are as follows:

     -f file     A custom configuration file may be used instead of the
                 default one: /usr/local/etc/monitord.conf.

     -t interval
                 The time interval in seconds at which to check the system
                 processes, which are configured in monitord.conf. The default
                 interval is 10 seconds.

     The configuration file for monitord, /usr/local/etc/monitord.conf, has a
     simple format. It is divided into two parts. The first part contains
     general configuration informaion, which for now consists simply of the
     admin's email and your email server. The second part consists of multiple
     configuration lines for each service to be monitored. In this second
     part, the first column contains the user under which the given service on
     that line will be run if it needs to be restarted. The group to which the
     user belongs will be grabbed from the password database.

     The second column consists of the options to be used in monitoring that
     particular service. Currently, three options are supported:

     auto        Indicates that the service should be automatically restarted
                 if it's found down. This is also the default behaviour when
                 neither auto nor noauto are specified.

     noauto      Indicates that the service should not be automatically
                 restarted if it's down.

     alert       Indicates that if this service is found down, the
                 administrator is automatically notified via email, as
                 specified in the first part of the configuration file. Also,
                 once a service is restarted, this option will prompt monitord
                 to notify the administrator that it was successfully
                 restarted.

     The third column is the delay that will follow the startup of that
     particular service. Some services take a while to start up, especially if
     they need to perform preperatory tasks in a wrapper script, so to keep
     monitord from attempting to restart a service after it's already begun
     its startup proceedure but before it appears in the process table the
     specified delay keeps monitord from checking that service for the
     specified time in seconds.

     The fourth and fifth columns are the service being monitored and script
     used to start the service, respectively. Only the script column includes
     the full path. If no special wrapper script is being used but instead the
     service's binary is invoked directly simply include the path to the
     service in the script column. The service field should always contain the
     name of the binary being executed. See examples in monitord.conf.

     The last column, which is optional, may contain any parameters that
     should be passed to the script (or binary as the case may be). For
     instance, the following line would configure monitord to watch for
     sendmail(8) and restart it, in case of termination, with the user root
     and group wheel (which it would grab from the password database), and
     then notify the administrator.  monitord will wait 30 seconds after
     attempting to restart sendmail before it checks to see if sendmail is up
     and running:

     root    auto,alert      30      sendmail        /usr/sbin/sendmail -bd -q60m


EXAMPLES

     Here are a few more example service entries:

     root    auto,alert      30      syslogd         /usr/sbin/inetd        -wW
     root    auto,alert      30      syslogd         /usr/sbin/syslogd
     www     auto,alert      60      httpd           /usr/local/etc/rc.d/apache.sh


IMPLEMENTATION NOTES

     This is version 0.4.1.

     When using a time interval that is smaller than 5 seconds, an
     increasingly larger amount of CPU time will be used by the process. It is
     recommended that one keep the interval equal to or above 5 seconds. The
     default of 10 seconds may be changed in config.h before compile time.


FILES

     /usr/local/etc/monitord.conf  configuration file


DIAGNOSTICS

     When restarting a service which it is monitoring, monitord will notify
     syslogd(8) of the event.

     monitord should be run as root so that it can restart the services it is
     monitoring with the correct username and group.


AUTHOR

     This manual page was written by W. M. Shandruk <walt@erudition.net>.


BUGS

     There are no known bugs.

FreeBSD 4.3                     August 21, 2003                    FreeBSD 4.3

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