Nagios

Time Periods

or...
"Is This a Good Time?"

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See Also See Also: On-Call Rotations, Host Checks, Service Checks, Notifications, Notification Escalations, Dependencies

Introduction

Timeperiods

Timeperiod definitions allow you to control when various aspects of the monitoring and alerting logic can operate. For instance, you can restrict:

Precedence in Time Periods

Timeperod definitions may contain multiple types of directives, including weekdays, days of the month, and calendar dates. Different types of directives have different precendence levels and may override other directives in your timeperiod definitions. The order of precedence for different types of directives (in descending order) is as follows:

Examples of different timeperiod directives can be found here.

How Time Periods Work With Host and Service Checks

Host and service definitions have an optional check_period directive that allows you to specify a timeperiod that should be used to restrict when regularly scheduled, active checks of the host or service can be made.

If you do not use the check_period directive to specify a timeperiod, Nagios will be able to schedule active checks of the host or service anytime it needs to. This is essentially a 24x7 monitoring scenario.

Specifying a timeperiod in the check_period directive allows you to restrict the time that Nagios perform regularly scheduled, active checks of the host or service. When Nagios attempts to reschedule a host or service check, it will make sure that the next check falls within a valid time range within the defined timeperiod. If it doesn't, Nagios will adjust the next check time to coincide with the next "valid" time in the specified timeperiod. This means that the host or service may not get checked again for another hour, day, or week, etc.

Note Note: On-demand checks and passive checks are not restricted by the timeperiod you specify in the check_period directive. Only regularly scheduled active checks are restricted.

Unless you have a good reason not to do so, I would recommend that you monitor all your hosts and services using timeperiods that cover a 24x7 time range. If you don't do this, you can run into some problems during "blackout" times (times that are not valid in the timeperiod definition):

  1. The status of the host or service will appear unchanged during the blackout time.
  2. Contacts will mostly likely not get re-notified of problems with a host or service during blackout times.
  3. If a host or service recovers during a blackout time, contacts will not be immediately notified of the recovery.

How Time Periods Work With Contact Notifications

By specifying a timeperiod in the notification_period directive of a host or service definition, you can control when Nagios is allowed to send notifications out regarding problems or recoveries for that host or service. When a host notification is about to get sent out, Nagios will make sure that the current time is within a valid range in the notification_period timeperiod. If it is a valid time, then Nagios will attempt to notify each contact of the problem or recovery.

You can also use timeperiods to control when notifications can be sent out to individual contacts. By using the service_notification_period and host_notification_period directives in contact definitions, you're able to essentially define an "on call" period for each contact. Contacts will only receive host and service notifications during the times you specify in the notification period directives.

Examples of how to create timeperiod definitions for use for on-call rotations can be found here.

How Time Periods Work With Notification Escalations

Service and host notification escalations have an optional escalation_period directive that allows you to specify a timeperiod when the escalation is valid and can be used. If you do not use the escalation_period directive in an escalation definition, the escalation is considered valid at all times. If you specify a timeperiod in the escalation_period directive, Nagios will only use the escalation definition during times that are valid in the timeperiod definition.

How Time Periods Work With Dependencies

Service and host dependencies have an optional dependency_period directive that allows you to specify a timeperiod when the dependendies are valid and can be used. If you do not use the dependency_period directive in a dependency definition, the dependency can be used at any time. If you specify a timeperiod in the dependency_period directive, Nagios will only use the dependency definition during times that are valid in the timeperiod definition.