XenServer

Upgrade from Corosync 2 to Corosync 3

Prerequisites

Before starting:

  • Shut down all virtual machines (VMs) that use GFS2 SRs.
  • Verify that High Availability (HA) is disabled.
  • Confirm that the host pool is healthy.
  • Ensure all hosts run XenServer 8.4.

Manual Upgrade Procedure

To transition from Corosync 2 to Corosync 3, follow the steps below:

  1. Shut down all VMs that are using a GFS2 Storage Repository (SR). This includes any VM with a Virtual Disk Image (VDI) located on a GFS2 SR.

  2. Detach all GFS2 SRs in the pool. In XenCenter, right-click the GFS2 SR and click Detach….

  3. Disable clustering. In XenCenter, right-click the pool or standalone server node, go to PropertiesClustering, and uncheck Enable clustering.

  4. Once clustering is disabled, recreate the cluster by re-enabling clustering via the same menu.

  5. Reattach the GFS2 SRs by right-clicking each SR and selecting Repair….

  6. Start any required VMs to resume normal operations.

Note:

After completing these steps, the cluster will be running on Corosync 3. The upgrade process is now complete.

Upgrade Procedure using CLI

Use this process to upgrade from Corosync 2 to Corosync 3 using CLI.

  1. Identify GFS2 SRs.

    xe sr-list type=gfs2
    <!--NeedCopy-->
    
  2. List VMs using each SR.

    xe vdi-list sr-uuid=<gfs2-sr-uuid> params=vbd-uuids
    xe vbd-list uuid=<vbd-uuid> params=vm-uuid
    <!--NeedCopy-->
    
  3. Shut Down affected VMs.

    xe vm-shutdown uuid=<vm-uuid>
    <!--NeedCopy-->
    
  4. Unplug SRs.

    xe sr-list type=gfs2 params=PBDs
    xe pbd-unplug uuid=<pbd-uuid>
    <!--NeedCopy-->
    
  5. Destroy the Cluster.

    xe cluster-pool-destroy uuid=<cluster-uuid>
    <!--NeedCopy-->
    
  6. Recreate the Cluster with Corosync 3.

    xe cluster-pool-create network-uuid=<network-uuid>
    <!--NeedCopy-->
    
  7. Reattach SRs.

    xe pbd-plug uuid=<pbd-uuid>
    <!--NeedCopy-->
    
  8. Start VMs for the Cluster to run Corosync 3.

    xe vm-start vm=<vm-uuid> on=<host-uuid>
    <!--NeedCopy-->
    

Configuration Requirements

  • No additional configuration is required.

  • Corosync 3 will be automatically used when a new cluster is created.

Compatibility Notes and Considerations

Citrix Virtual Apps and Desktops (CVAD)

If CVAD is used to manage VMs, ensure hosts are placed in maintenance mode or confirm that VMs will not restart on GFS2 SRs during shutdown (Step 1).

Maintenance Planning

Steps 1 and 2 may be time-consuming. For example, a test involving 16 hosts and 62 SRs took approximately 6 hours. Plan a suitable maintenance window accordingly.

Upgrade Enforcement

This upgrade is mandatory before moving on from XenServer 8.4. The Rolling Pool Upgrade (RPU) plugin will block upgrades from XenServer 8.4 to a greater version if the Corosync upgrade has not been completed. XenCenter will display warnings based on cluster usage.

Upgrade from Corosync 2 to Corosync 3