7. Administrative Modes

Intrusive administration can be performed on a Pacemaker cluster without causing resource failures, recovery, and fencing, by putting the cluster or a subset of it into an administrative mode.

Pacemaker supports several administrative modes:

  • Maintenance mode for the entire cluster, specific nodes, or specific resources
  • Unmanaged resources
  • Disabled configuration items
  • Standby mode for specific nodes

Rules may be used to automatically set any of these modes for specific times or other conditions.

7.1. Maintenance Mode

In maintenance mode, the cluster will not start or stop resources. Recurring monitors for affected resources will be paused, except those specifying role as Stopped.

To put a specific resource into maintenance mode, set the resource’s maintenance meta-attribute to true.

To put all active resources on a specific node into maintenance mode, set the node’s maintenance node attribute to true. When enabled, this overrides resource-specific maintenance mode.

Warning

Restarting Pacemaker on a node that is in single-node maintenance mode will likely lead to undesirable effects. If maintenance is set as a transient attribute, it will be erased when Pacemaker is stopped, which will immediately take the node out of maintenance mode and likely get it fenced. If set as a permanent attribute, any resources active on the node will have their local history erased when Pacemaker is restarted, so the cluster will no longer consider them running on the node and thus will consider them managed again, allowing them to be started elsewhere.

To put all resources in the cluster into maintenance mode, set the maintenance-mode cluster option to true. When enabled, this overrides node- or resource- specific maintenance mode.

Maintenance mode, at any level, overrides other administrative modes.

7.2. Unmanaged Resources

An unmanaged resource will not be started or stopped by the cluster. A resource may become unmanaged in several ways:

  • The administrator may set the is-managed resource meta-attribute to false (whether for a specific resource, or all resources without an explicit setting via rsc_defaults)
  • Maintenance mode causes affected resources to become unmanaged (and overrides any is-managed setting)
  • Certain types of failure cause affected resources to become unmanaged. These include:
    • Failed stop operations when the stonith-enabled cluster property is set to false
    • Failure of an operation that has on-fail set to block
    • A resource detected as incorrectly active on more than one node when its multiple-active meta-attribute is set to block
    • A resource constrained by a revoked rsc_ticket with loss-policy set to freeze
    • Resources with requires set (or defaulting) to anything other than nothing in a partition that loses quorum when the no-quorum-policy cluster option is set to freeze

Recurring actions are not affected by unmanaging a resource.

Warning

Manually starting an unmanaged resource on a different node is strongly discouraged. It will at least cause the cluster to consider the resource failed, and may require the resource’s target-role to be set to Stopped then Started in order for recovery to succeed.

7.3. Disabled Configuration

Some configuration elements disable particular behaviors:

  • The stonith-enabled cluster option, when set to false, disables node fencing. This is highly discouraged, as it can lead to data unavailability, loss, or corruption.
  • The stop-all-resources cluster option, when set to true, causes all resources to be stopped.
  • Certain elements support an enabled meta-attribute, which if set to false, causes the cluster to act as if the specific element is not configured. These include op, alert (since 2.1.6), and recipient (since 2.1.6). enabled may be set for specific op elements, or all operations without an explicit setting via op_defaults.

7.4. Standby Mode

When a node is put into standby, all resources will be moved away from the node, and all recurring operations will be stopped on the node, except those specifying role as Stopped (which will be newly initiated if appropriate).

A node may be put into standby mode by setting its standby node attribute to true. The attribute may be queried and set using the crm_standby tool.

7.5. Rules

Rules may be used to set administrative mode options automatically according to various criteria such as date and time. See the “Rules” chapter of the Pacemaker Explained document for details.