Main Configuration File Options


Notes

When creating and/or editing configuration files, keep the following in mind:

  1. Lines that start with a '#' character are taken to be comments and are not processed
  2. Variables names must begin at the start of the line - no white space is allowed before the name
  3. Variable names are case-sensitive

Sample Configuration

A sample main configuration file can be created by running the 'make config' command. The default name of the main configuration file is netsaint.cfg - look for it in the NetSaint distribution directory or in the etc/ subdirectory of your installation.

Index

Log file
Host configuration file
Status file
Temp file
Program mode
Log rotation method
Log archive path
External command check option
External command check interval
External command file
Log severity level
Syslog logging option
Syslog severity level
Notification logging option
Service check retry logging option
Host retry logging option
Event handler logging option
Global host event handler
Global service event handler
Inter-check sleep time
Inter-check delay method
Service interleave factor
Maximum concurrent service checks
Service reaper frequency
Timing interval length
Agressive host checking option
Generic service notification summary
Administrator email address
Administrator pager

Log File

Format: log_file=<file_name>
Example: log_file=/usr/local/netsaint/var/netsaint.log

This variable specifies where NetSaint should create its main log file. This should be the first variable that you define in your configuration file, as NetSaint will try to write errors that it finds in the rest of your configuration data to this file. This file is never deleted, pruned or rotated by NetSaint. I suggest adding a cron job to do log rotations every month or so (more often if you have a lot of alarms).

Host Configuration File

Format: cfg_file=<file_name>
Example: cfg_file=/usr/local/netsaint/etc/hosts.cfg

This specifies the host configuration file that NetSaint should use for monitoring. Host configuration files contain configuration data for hosts, host groups, contacts, contact groups, services, commands, etc. You can split your configuration information into several files and specify multiple cfg_file= statements to include each of them.

Status File

Format: status_file=<file_name>
Example: status_file=/usr/local/netsaint/var/status.log

This is the file that NetSaint uses to store the current status of all monitored services. The status of all hosts associated with the service you monitor are also recorded here. This file is used by the "status" CGI so that current monitoring status can be reported via a web interface. The CGIs must have read access to this file in order to function properly. This file is deleted every time NetSaint stops and recreated when it starts.

Temp File

Format: temp_file=<file_name>
Example: temp_file=/usr/local/netsaint/var/netsaint.tmp

This is the temporary file into which NetSaint redirects the standard output and error from the execution of plugins. The output from the plugins is scooped from the temp file and used for both display in the "status" CGI output and use in notification macros. This file is deleted after the plugin has been executed. This file is also used as a scratch file when NetSaint updates the status log.

Note: On most systems, the temp file will have to reside on the same filesystem as the status file, the log file, and the log file archive path.

Program Mode

Format: program_mode=<a/s>
Example: program_mode=a

This is the intial program mode that NetSaint should use when it starts or restarts. More information on program modes can be found here. Values are as follows:

Log Rotation Method

Format: log_rotation_method=<n/h/d/w/m>
Example: log_rotation_method=d

This is the rotation method that you would like NetSaint to use for your log file. Values are as follows:

Log Archive Path

Format: log_archive_path=<path>
Example: log_archive_path=/usr/local/netsaint/var/archives/

This is the directory where NetSaint should place log files that have been rotated. This option is ignored if you choose to not use the log rotation functionality.

External Command Check Option

Format: check_external_commands=<0/1>
Example: check_external_commands=1

This option determines whether or not NetSaint will check the command file for internal commands it should execute. This option must be enabled if you plan on using the command CGI to issue commands via the web interface. Third party programs can also issue commands to NetSaint by writing to the command file, provided proper rights to the file have been granted as outlined in this FAQ. More information on external commands can be found here.

External Command Check Interval

Format: command_check_interval=<xxx>
Example: command_check_interval=1

This is the number of "time units" to wait between external command checks. Unless you've changed the interval_length value (as defined below) from the default value of 60, this number will mean minutes. Each time NetSaint checks for external commands it will read and process all commands present in the command file before continuing on with its other duties. More information on external commands can be found here.

External Command File

Format: command_file=<file_name>
Example: command_file=/usr/local/netsaint/var/rw/netsaint.cmd

This is the file that NetSaint will check for external commands to process. The command CGI writes commands to this file. Other third party programs can write to this file if proper file permissions have been granted as outline in this FAQ. More information on external commands can be found here.

Log Severity Level

Format: log_level=<1-2>
Example: log_level=1

This is the level of severity needed for service messages to be logged to the main log file. Values are as follows:

Notes:

Syslog Logging Option

Format: use_syslog=<0/1>
Example: use_syslog=1

This variable determines whether messages are logged to the syslog facility on your local host. Values are as follows:

Syslog Severity Level

Format: syslog_level=<1-2>
Example: syslog_level=1

This is the level of severity needed for service messages to be logged to the syslog facility. Values are as follows:

Notes:

Notification Logging Option

Format: log_notifications=<0/1>
Example: log_notifications=1

This variable determines whether or not notification messages are logged. If you have a lot of contacts or regular service failures your log file will grow relatively quickly. Use this option to keep contact notifications from being logged.

Service Check Retry Logging Option

Format: log_service_retries=<0/1>
Example: log_service_retries=1

This variable determines whether or not service check retries are logged. Service check retries occur when a service check results in a non-OK state, but you have configured NetSaint to retry the service more than once before responding to the error. Services in this situation are considered to be in "soft" states. Logging service check retries is mostly useful when attempting to debug NetSaint or test out service event handlers.

Host Check Retry Logging Option

Format: log_host_retries=<0/1>
Example: log_host_retries=1

This variable determines whether or not host check retries are logged. Logging host check retries is mostly useful when attempting to debug NetSaint or test out host event handlers.

Event Handler Logging Option

Format: log_event_handlers=<0/1>
Example: log_event_handlers=1

This variable determines whether or not service and host event handlers are logged. Event handlers are optional commands that can be run whenever a service or hosts changes state. Logging event handlers is most useful when debuggin NetSaint or first trying out your event handler scripts.

Global Host Event Handler Option

Format: global_host_event_handler=<command>
Example: global_host_event_handler=log-host-event-to-db

This option allows you to specify a host event handler command that is to be run for every host state change. The global event handler is executed immediately prior to the event handler that you have optionally specified in each host definition. The command argument is the short name of a command definition that you define in your host configuration file. More information on event handlers can be found here.

Global Service Event Handler Option

Format: global_service_event_handler=<command>
Example: global_service_event_handler=log-service-event-to-db

This option allows you to specify a service event handler command that is to be run for every service state change. The global event handler is executed immediately prior to the event handler that you have optionally specified in each service definition. The command argument is the short name of a command definition that you define in your host configuration file. More information on event handlers can be found here.

Inter-Check Sleep Time

Format: sleep_time=<seconds>
Example: sleep_time=1

This is the number of seconds that NetSaint will sleep before checking to see if the next service check in the scheduling queue should be executed. Note that NetSaint will only sleep after it "catches up" with queued service checks that have fallen behind.

Inter-Check Delay Method

Format: inter_check_delay_method=<n/d/s>
Example: inter_check_delay_method=s

This option allows you to control how service checks are initially "spread out" in the event queue. Using a "smart" delay calculation (the default) will cause NetSaint to calculate an average check interval and spread initial checks of all services out over that interval, thereby helping to eliminate CPU load spikes. Using no delay is generally not recommended unless you are testing the service check parallelization functionality. Using no delay will cause all service checks to be scheduled for execution at the same time. This means that you will generally have large CPU spikes when the services are all executed in parallel. Values are as follows:

Service Interleave Factor

Format: service_interleave_factor=<s|n>
Example: service_interleave_factor=s

This variable determines how service checks are interleaved. Interleaving allows for a more even distribution of service checks, reduced load on remote hosts, and faster overall detection of host problems. With the introduction of service check parallelization, remote hosts could get bombarded with checks if interleaving was not implemented. This could cause the service checks to fail or return incorrect results if the remote host was overloaded with processing other service check requests. Setting this value to 1 is equivalent to not interleaving the service checks (this is how versions of NetSaint previous to 0.0.5 worked). Set this value to s (smart) for automatic calculation of the interleave factor unless you have a specific reason to change it. The best way to understand how interleaving works is to watch the status CGI (detailed view) when NetSaint is just starting. You should see that the service check results are spread out as they begin to appear.

Maximum Concurrent Service Checks

Format: max_concurrent_checks=<max_checks>
Example: max_concurrent_checks=20

This option allows you to specify the maximum number of service checks that can be run in parallel at any given time. Specifying a value of 1 for this variable essentially prevents any service checks from being parallelized. You'll have to modify this value based on the system resources you have available on the machine that runs NetSaint, as it directly affects the maximum load that will be imposed on the system (processor utilization, memory, etc.).

Service Reaper Frequency

Format: service_reaper_frequency=<frequency_in_seconds>
Example: service_reaper_frequency=10

This option allows you to control the frequency in seconds of service "reaper" events. "Reaper" events process the results from parallelized service checks that have finished executing. These events consitute the core of the monitoring logic in NetSaint.

Timing Interval Length

Format: interval_length=<seconds>
Example: interval_length=60

This is the number of seconds per "unit interval" used for timing in the scheduling queue, re-notifications, etc. "Units intervals" are used in the host configuration file to determine how often to run a service check, how often of re-notify a contact, etc.

Important: The default value for this is set to 60, which means that a "unit value" of 1 in the host configuration file will mean 60 seconds (1 minute). I have not really tested other values for this variable, so proceed at your own risk if you decide to do so!

Agressive Host Checking Option

Format: use_agressive_host_checking=<0/1>
Example: use_agressive_host_checking=0

Beginning with release 0.0.4, NetSaint tries to be a little smarter about how and when it checks the status of hosts. In general, disabling this option will allow NetSaint to make some smarter decisions and check hosts a bit faster. Enabling this option will increase the amount of time required to check hosts, but may improve reliability a bit. If you want to know more about exactly what this option does, search the source code in the netsaint.c file for the string "use_agressive_host_checking" and read some of the comments I've added. Unless you have problems with NetSaint not recognizing that a host recovered, I would suggest not enabling this option.

Generic Service Notification Summary

Format: generic_summary=<notification_string_with_macros>
Example: generic_summary="***** NetSaint *****\n\n$SERVICESTATE$ alert/notification\n\nDate/Time: $DATETIME$\nService: $SERVICEDESC$\nHost: $HOSTALIAS$\nAddress: $HOSTADDRESS$\n\nAdditional Info:\n\n$OUTPUT$"

This is an optional generic service alert summary for use in service notification commands. If you define this variable you are able to use the $SUMMARY$ macro in notification messages. This is intended to help prevent wrist strain by not requiring you to have to type summary messages for each service notification command that is defined. Macros are allowed in the generic summary message. See the documentation on macros for information on what types of macros are "valid". Basically, any macro that is valid during a service notification can be used.

Administrator Email Address

Format: admin_email=<email_address>
Example: admin_email=root

This is the email address for the administrator of the local machine (i.e. the one that NetSaint is running on). This value can be used in notification commands by using the $ADMINEMAIL$ macro.

Administrator Pager

Format: admin_pager=<pager_number_or_pager_email_gateway>
Example: admin_pager=pageroot@pagenet.com

This is the pager number (or pager email gateway) for the administrator of the local machine (i.e. the one that NetSaint is running on). The pager number/address can be used in notification commands by using the $ADMINPAGER$ macro.