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6.6. 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 6.4, “Properties of an Operation” summarizes the properties of a resource monitoring operation.

Table 6.4. 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
If set to a nonzero value, a recurring operation is created that repeats at this frequency, in seconds. A nonzero value makes sense only when the action name is set to monitor. A recurring monitor action will be executed immediately after a resource start completes, and subsequent monitor actions are scheduled starting at the time the previous monitor action completed. For example, if a monitor action with interval=20s is executed at 01:00:00, the next monitor action does not occur at 01:00:20, but at 20 seconds after the first monitor action completes.
If set to zero, which is the default value, this parameter allows you to provide values to be used for operations created by the cluster. For example, if the interval is set to zero, the name of the operation is set to start, and the timeout value is set to 40, then Pacemaker will use a timeout of 40 seconds when starting this resource. A monitor operation with a zero interval allows you to set the timeout/on-fail/enabled values for the probes that Pacemaker does at startup to get the current status of all resources when the defaults are not desirable.
timeout
If the operation does not complete in the amount of time set by this parameter, abort the operation and consider it failed. The default value is the value of timeout if set with the pcs resource op defaults command, or 20 seconds if it is not set. If you find that your system includes a resource that requires more time than the system allows to perform an operation (such as start, stop, or monitor), investigate the cause and if the lengthy execution time is expected you can increase this value.
The timeout value is not a delay of any kind, nor does the cluster wait the entire timeout period if the operation returns before the timeout period has completed.
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

6.6.1. Configuring Resource Operations

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 can update the resource. 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)
To change the stop timeout operation, execute the following command.
# pcs resource update VirtualIP op 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)

Note

When you update a resource's operation with the pcs resource update command, any options you do not specifically call out are reset to their default values.

6.6.2. Configuring Global Resource Operation Defaults

You can use the following command to set global default values for monitoring operations.
pcs resource op defaults [options]
For example, the following command sets a global default of a timeout value of 240 seconds 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 240 seconds.
# pcs resource op defaults
timeout: 240s
Note that a cluster resource will use the global default only when the option is not specified in the cluster resource definition. By default, resource agents define the timeout option for all operations. For the global operation timeout value to be honored, you must create the cluster resource without the timeout option explicitly or you must remove the timeout option by updating the cluster resource, as in the following command.
# pcs resource update VirtualIP op monitor interval=10s
For example, after setting a global default of a timeout value of 240 seconds for all monitoring operations and updating the cluster resource VirtualIP to remove the timeout value for the monitor operation, the resource VirtualIP will then have timeout values for start, stop, and monitor operations of 20s, 40s and 240s, respectively. The global default value for timeout operations is applied here only on the monitor operation, where the default timeout option was removed by the previous command.
# 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 (VirtualIP-monitor-interval-10s)
               stop interval=0s timeout=40s (VirtualIP-name-stop-interval-0s-timeout-40s)