5.8.2. Multiple Monitor Operations

Provided no two operations (for a single resource) have the same name and interval you can have as many monitor operations as you like. In this way you can do a superficial health check every minute and progressively more intense ones at higher intervals.

To tell the resource agent what kind of check to perform, you need to provide each monitor with a different value for a common parameter. The OCF standard creates a special parameter called OCF_CHECK_LEVEL for this purpose and dictates that it is made available to the resource agent without the normal OCF_RESKEY_ prefix.

Whatever name you choose, you can specify it by adding an instance_attributes block to the op tag. Note that it is up to each resource agent to look for the parameter and decide how to use it.

Example 5.9. An OCF resource with two recurring health checks performing different levels of checks


  <primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
    <operations>
     <op id="public-ip-health-60" name="monitor" interval="60">
       <instance_attributes id="params-public-ip-depth-60">
           <nvpair id="public-ip-depth-60" name="OCF_CHECK_LEVEL" value="10"/>
       </instance_attributes>
     </op>
     <op id="public-ip-health-300" name="monitor" interval="300">
       <instance_attributes id="params-public-ip-depth-300">
           <nvpair id="public-ip-depth-300" name="OCF_CHECK_LEVEL" value="20"/>
       </instance_attributes>
     </op>
    </operations>
    <instance_attributes id="params-public-ip">
       <nvpair id="public-ip-level" name="ip" value="1.2.3.4"/>
    </instance_attributes>
  </primitive>