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5.6. Resource Operations

To ensure that resources remain healthy, you can add a monitoring operation to a resource's definition. If you do not specify a monitoring operation for a resource, by default the pcs command will create a monitoring operation, with an interval that is determined by the resource agent. If the resource agent does not provide a default monitoring interval, the pcs command will create a monitoring operation with an interval of 60 seconds.
Table 5.4, “Properties of an Operation” summarizes the properties of a resource monitoring operation.

Table 5.4. Properties of an Operation

FieldDescription
id
Unique name for the action. The system assigns this when you configure an operation.
name
The action to perform. Common values: monitor, start, stop
interval
How frequently (in seconds) to perform the operation. Default value: 0, meaning never.
timeout
How long to wait before declaring the action has failed. If you find that your system includes a resource that takes a long time to start or stop or perform a non-recurring monitor action at startup, and requires more time than the system allows before declaring that the start action has failed, you can increase this value from the default of 20 or the value of timeout in "op defaults".
on-fail
The action to take if this action ever fails. Allowed values:
* ignore - Pretend the resource did not fail
* block - Do not perform any further operations on the resource
* stop - Stop the resource and do not start it elsewhere
* restart - Stop the resource and start it again (possibly on a different node)
* fence - STONITH the node on which the resource failed
* standby - Move all resources away from the node on which the resource failed
The default for the stop operation is fence when STONITH is enabled and block otherwise. All other operations default to restart.
enabled
If false, the operation is treated as if it does not exist. Allowed values: true, false
You can configure monitoring operations when you create a resource, using the following command. 
pcs resource create resource_id standard:provider:type|type [resource_options] [op operation_action operation_options [operation_type operation_options]...]
For example, the following command creates an IPaddr2 resource with a monitoring operation. The new resource is called VirtualIP with an IP address of 192.168.0.99 and a netmask of 24 on eth2. A monitoring operation will be performed every 30 seconds. 
# pcs resource create VirtualIP ocf:heartbeat:IPaddr2 ip=192.168.0.99 cidr_netmask=24 nic=eth2 op monitor interval=30s
Alternately, you can add a monitoring operation to an existing resource with the following command. 
pcs resource op add resource_id operation_action [operation_properties]
Use the following command to delete a configured resource operation. 
pcs resource op remove resource_id operation_name operation_properties

Note

You must specify the exact operation properties to properly remove an existing operation.
To change the values of a monitoring option, you remove the existing operation, then add the new operation. For example, you can create a VirtualIP with the following command. 
# pcs resource create VirtualIP ocf:heartbeat:IPaddr2 ip=192.168.0.99 cidr_netmask=24 nic=eth2
By default, this command creates these operations. 
Operations: start interval=0s timeout=20s (VirtualIP-start-timeout-20s)
            stop interval=0s timeout=20s (VirtualIP-stop-timeout-20s)
            monitor interval=10s timeout=20s (VirtualIP-monitor-interval-10s)
The change the stop timeout operation, execute the following commands. 
# pcs resource op remove VirtualIP stop interval=0s timeout=20s
# pcs resource op add VirtualIP stop interval=0s timeout=40s

# pcs resource show VirtualIP
 Resource: VirtualIP (class=ocf provider=heartbeat type=IPaddr2)
  Attributes: ip=192.168.0.99 cidr_netmask=24 nic=eth2
  Operations: start interval=0s timeout=20s (VirtualIP-start-timeout-20s)
              monitor interval=10s timeout=20s (VirtualIP-monitor-interval-10s)
              stop interval=0s timeout=40s (VirtualIP-name-stop-interval-0s-timeout-40s)
To set global default values for monitoring operations, use the following command. 
pcs resource op defaults [options]
For example, the following command sets a global default of a timeout value of 240s for all monitoring operations. 
# pcs resource op defaults timeout=240s
To display the currently configured default values for monitoring operations, do not specify any options when you execute the pcs resource op defaults command.
For example, following command displays the default monitoring operation values for a cluster which has been configured with a timeout value of 240s. 
# pcs resource op defaults
timeout: 240s