How to set Pacemaker cluster properties with PCS

Cluster properties define key cluster-wide behaviors in Pacemaker, including failure handling, quorum behavior, and safety controls like STONITH fencing.

Properties are stored in the cluster configuration database (CIB) and read by the Pacemaker controller and scheduler on every node. Running pcs property set updates the CIB, causing the new value to take effect across the cluster without editing files on individual nodes.

Safety-impacting properties such as stonith-enabled and no-quorum-policy can stop resources or permit split-brain conditions when misused. Record the current value before changes, apply changes deliberately, and ensure a rollback path exists if a property change produces unexpected behavior.

1. Review current cluster properties, including defaults.

   $ sudo pcs property config --all
   Cluster Properties: cib-bootstrap-options
     cluster-infrastructure=corosync
     cluster-name=clustername
   ##### snipped #####
     maintenance-mode=false (default)
     no-quorum-policy=stop (default)
     stonith-enabled=false
   ##### snipped #####

   Properties shown here apply cluster-wide and can affect scheduling and recovery immediately.

2. Check the current value of the property being changed.

   $ sudo pcs property config stonith-enabled
   Cluster Properties: cib-bootstrap-options
     stonith-enabled=false

   Keep the current value for rollback if the change needs to be reverted quickly.

3. Set the cluster property to the required value.

   $ sudo pcs property set stonith-enabled=false

   Disabling stonith-enabled reduces fencing protection and can permit split-brain conditions during network partitions.

4. Verify the updated property value in the cluster configuration.

   $ sudo pcs property config stonith-enabled
   Cluster Properties: cib-bootstrap-options
     stonith-enabled=false

5. Confirm the cluster remains healthy after the property change.

   $ sudo pcs status
   Cluster name: clustername
   Cluster Summary:
     * Stack: corosync (Pacemaker is running)
     * Current DC: node-03 (version 2.1.6-6fdc9deea29) - partition with quorum
     * Last updated: Wed Dec 31 08:27:24 2025 on node-01
     * Last change:  Wed Dec 31 08:26:43 2025 by root via cibadmin on node-01
     * 3 nodes configured
     * 2 resource instances configured
   
   Node List:
     * Online: [ node-01 node-02 node-03 ]
   
   Full List of Resources:
     * cluster_ip (ocf:heartbeat:IPaddr2): Started node-01
     * web-service (systemd:nginx): Started node-02
   
   Daemon Status:
     corosync: active/enabled
     pacemaker: active/enabled
     pcsd: active/enabled