icinga2/doc/3.03-macros.md

Macros

Note

There is a limited set of special global constants which can be re-used and also partly overridden such as IcingaEnableChecks.

Runtime Macros

Macros may be used in command definitions to dynamically change how the command is executed. Additionally there are Icinga 2 features for example the PerfDataWriter using the available runtime macros for output formatting.

Note

Macros are evaluated at runtime when executing a command. These macros cannot be used inside the configuration objects to add references or similar unless stated otherwise.

Here is an example of a command definition which uses user-defined macros:

object CheckCommand "my-ping" inherits "plugin-check-command" {
  command = [
    "$plugindir$/check_ping",
    "-4",
    "-H", "$address$",
    "-w", "$wrta$,$wpl$%",
    "-c", "$crta$,$cpl$%",
    "-p", "$packets$",
    "-t", "$timeout$"
  ],

  macros = {
    wrta = 100,
    wpl = 5,

    crta = 200,
    cpl = 15,

    packets = 5,
    timeout = 0
  }
}

Note

If you have previously used Icinga 1.x you may already be familiar with user and argument macros (e.g., USER1 or ARG1). Unlike in Icinga 1.x macros may have arbitrary names and arguments are no longer specified in the check_command setting.

Macro names must be enclosed in two $ signs, e.g. $plugindir$. When using the $ sign as single character, you need to escape it with an additional dollar sign ($$).

Runtime Macro Evaluation Order

When executing commands Icinga 2 checks the following objects in this order to look up macros:

1. User object (only for notifications)
2. Service object
3. Host object
4. Command object
5. Global macros in the IcingaMacros constant

This execution order allows you to define default values for macros in your command objects. The my-ping command shown above uses this to set default values for some of the latency thresholds and timeouts.

When using the my-ping command you can override all or some of the macros in the service definition like this:

object Host "my-server1" {
  services["ping"] = {
    check_command = "my-ping",

    macros["packets"] = 10 // Overrides the default value of 5 given in the command
  },

  macros["address"] = "10.0.0.1"
}

If a macro isn't defined anywhere an empty value is used and a warning is emitted to the Icinga 2 log.

Note

Macros in capital letters (e.g. HOSTNAME) are reserved for use by Icinga 2 and should not be overwritten by users.

Best Practice

By convention every host should have an address macro. Hosts which have an IPv6 address should also have an address6 macro.

The plugindir macro should be set to the path of your check plugins. The /etc/icinga2/conf.d/macros.conf file is usually used to define global macros including this one.

Custom Variables as Runtime Macros

Custom variables are made available as macros using an underscore and the object type in uppercase characters as additional prefix. For example _HOSTname "_HOST" where is the name of the custom variable.

Runtime Macro Evaluation Order in Cluster Mode

These macros are evaluated and calculated upon command execution on each node. If a cluster node defines additional macros overriding the default tuples, the calculated macro values will be different and affect only the node executing the command.

Node 1:

const IcingaMacros = {
  plugindir = "/usr/lib/icinga/plugins"
}

Node 2:

const IcingaMacros = {
  plugindir = "/usr/lib/monitoring/plugins"
}

CheckCommand definition:

object CheckCommand "whatever" inherits "plugin-check-command" {
   command = "$plugindir$/check_whatever"
}

On Node 1, this will be evaluated into /usr/lib/icinga/plugins/check_whatever. On Node 2, Icinga 2 will attempt to execute /usr/lib/icinga/monitoring/check_whatever instead.

Host Runtime Macros

The following host macros are available in all commands that are executed for hosts or services:

Name	Description
HOSTNAME	The name of the host object.
HOSTDISPLAYNAME	The value of the display_name attribute.
HOSTALIAS	This is an alias for the HOSTDISPLAYNAME macro.
HOSTSTATE	The host's current state. Can be one of UNREACHABLE, UP and DOWN.
HOSTSTATEID	The host's current state. Can be one of 0 (up), 1 (down) and 2 (unreachable).
HOSTSTATETYPE	The host's current state type. Can be one of SOFT and HARD.
HOSTATTEMPT	The current check attempt number.
MAXHOSTATTEMPT	The maximum number of checks which are executed before changing to a hard state.
LASTHOSTSTATE	The host's previous state. Can be one of UNREACHABLE, UP and DOWN.
LASTHOSTSTATEID	The host's previous state. Can be one of 0 (up), 1 (down) and 2 (unreachable).
LASTHOSTSTATETYPE	The host's previous state type. Can be one of SOFT and HARD.
LASTHOSTSTATECHANGE	The last state change's timestamp.
HOSTDURATIONSEC	The time since the last state change.
HOSTLATENCY	The host's check latency.
HOSTEXECUTIONTIME	The host's check execution time.
HOSTOUTPUT	The last check's output.
HOSTPERFDATA	The last check's performance data.
LASTHOSTCHECK	The timestamp when the last check was executed.
HOSTADDRESS	This is an alias for the address macro. If the address macro is not defined the host object's name is used instead.
HOSTADDRESS6	This is an alias for the address6 macro. If the address macro is not defined the host object's name is used instead.

Note

HOSTADDRESS and HOSTADDRESS6 macros are available as legacy macros. The Icinga 2 Template Library (ITL) examples use the $address$ macro instead requiring that macro key to be defined.

Custom variables are made available as macros with the name "_HOST" where is the name of the custom variable.

Service Runtime Macros

The following service macros are available in all commands that are executed for services:

Name	Description
SERVICEDESC	The short name of the service object.
SERVICEDISPLAYNAME	The value of the display_name attribute.
SERVICECHECKCOMMAND	This is an alias for the SERVICEDISPLAYNAME macro.
SERVICESTATE	The service's current state. Can be one of OK, WARNING, CRITICAL and UNKNOWN.
SERVICESTATEID	The service's current state. Can be one of 0 (ok), 1 (warning), 2 (critical) and 3 (unknown).
SERVICESTATETYPE	The service's current state type. Can be one of SOFT and HARD.
SERVICEATTEMPT	The current check attempt number.
MAXSERVICEATTEMPT	The maximum number of checks which are executed before changing to a hard state.
LASTSERVICESTATE	The service's previous state. Can be one of OK, WARNING, CRITICAL and UNKNOWN.
LASTSERVICESTATEID	The service's previous state. Can be one of 0 (ok), 1 (warning), 2 (critical) and 3 (unknown).
LASTSERVICESTATETYPE	The service's previous state type. Can be one of SOFT and HARD.
LASTSERVICESTATECHANGE	The last state change's timestamp.
SERVICEDURATIONSEC	The time since the last state change.
SERVICELATENCY	The service's check latency.
SERVICEEXECUTIONTIME	The service's check execution time.
SERVICEOUTPUT	The last check's output.
SERVICEPERFDATA	The last check's performance data.
LASTSERVICECHECK	The timestamp when the last check was executed.
TOTALHOSTSERVICES	Number of services associated with the host.
TOTALHOSTSERVICESOK	Number of services associated with the host which are in an OK state.
TOTALHOSTSERVICESWARNING	Number of services associated with the host which are in a WARNING state.
TOTALHOSTSERVICESUNKNOWN	Number of services associated with the host which are in an UNKNOWN state.
TOTALHOSTSERVICESCRITICAL	Number of services associated with the host which are in a CRITICAL state.

Custom variables are made available as macros with the name "_SERVICE" where is the name of the custom variable.

User Runtime Macros

The following macros are available in all commands that are executed for users:

Name	Description
USERNAME	The name of the user object.
USERDISPLAYNAME	The value of the display_name attribute.
USEREMAIL	This is an alias for the email macro.
USERPAGER	This is an alias for the pager macro.

Custom variables are made available as macros with the name "_USER" and "_CONTACT" where is the name of the custom variable. "_CONTACT"

Notification Runtime Macros

Custom variables are made available as macros with the name "_NOTIFICATION" where is the name of the custom variable.

Global Runtime Macros

The following macros are available in all executed commands:

Name	Description
TIMET	Current UNIX timestamp.
LONGDATETIME	Current date and time including timezone information. Example: 2014-01-03 11:23:08 +0000
SHORTDATETIME	Current date and time. Example: 2014-01-03 11:23:08
DATE	Current date. Example: 2014-01-03
TIME	Current time including timezone information. Example: 11:23:08 +0000

Runtime Macros as Environment Variables

The export_macros command object attribute requires a list of macros which should be exported as environment variables prior to executing the command.

This is useful for example for hiding sensitive information on the command line output when passing credentials to database checks:

object CheckCommand "mysql-health" inherits "plugin-check-command" {
   command = "$plugindir$/check_mysql -H $address$ -d $db$",
   /* default macro values */
   macros = {
     "MYSQLUSER" = "icinga_check",
     "MYSQLPASS" = "1c1ng42r0xx"
   },

   export_macros = [
     "MYSQLUSER",
     "MYSQLPASS"
   ]
}

Configuration Macros

Icinga 2 allows you to define constants which can be used in a limited scope. For example, constant expressions can reference a pre-defined global constant variable and calculate a value for the service check interval.

Example:

const MyCheckInterval = 10m

...

{
  check_interval = MyCheckInterval / 2.5
}

More details in the chapter Constant Expressions.