icinga2/doc/3.05-using-templates.md

Using Templates

Templates may be used to apply a set of similar settings to more than one object.

For example, rather than manually creating a ping service object for each of your hosts you can use templates to avoid having to copy & paste parts of your configuration:

template Host "linux-server" {
  services["ping"] = {
    check_command = "ping4"
  },

  check = "ping"
}

object Host "my-server1" inherits "linux-server" {
  macros["address"] = "10.0.0.1"
}

object Host "my-server2" inherits "linux-server" {
  macros["address"] = "10.0.0.2"
}

In this example both my-server1 and my-server2 each get their own ping service check. Each host gets its own host check defined as the ping service too.

Objects as well as templates themselves can inherit from an arbitrary number of templates. Attributes inherited from a template can be overridden in the object if necessary.

Templates can also be used in service and notification definitions using the templates attribute:

template Service "weekend-service" {
  check_interval = 0.5m,
  check_period = "weekend"
}

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

templates = [ "weekend-service" ]
  }
}