XenCenter

VM Restart Settings

If more servers fail than have been planned for, then a high availability recovery operation begins. The HA restart priority is used to determine which VMs are restarted. The start order and delay interval values determine the order in which individual VMs are started. These settings ensure that the most important VMs are restarted first.

High availability restart priority

The HA restart priority specifies which VMs restart under the high availability failure plan for a pool:

  • Restart - VMs with this priority are guaranteed to be restarted if sufficient resources are available within the pool. They restart before VMs with a Restart if possible priority.

    All VMs with this restart priority are considered when calculating a failure plan. If no plan exists for which all VMs with this priority can reliably restart, the pool is overcommitted.

  • Restart if possible - VMs with this restart priority are not considered when calculating a failure plan. However, an attempt to restart these VMs is made if a server that is running them fails. This restart is attempted after all higher-priority VMs are restarted. If the attempt to start a restart-if-possible VM fails because there is not capacity to start the VM, it is not retried.

    This setting is useful for test/development VMs which aren’t critical to keep running, but would be nice to do so.

  • Do not restart - No attempts are made to restart VMs with this priority.

Start order

The Start order property specifies the order in which individual VMs start up during a recovery operation. This setting allows certain VMs to be started before others. VMs with a start order value of 0 (zero) start first, then VMs with a start order value of 1, and so on.

Delay interval (Attempt to start next VM after)

The Attempt to start next VM after property specifies how long the recovery process waits after the VMs start before starting the next VMs in the startup sequence. The next group of VMs are those VMs with a later start order.

XenServer 8

Citrix Hypervisor 8.2 Cumulative Update 1

VM Restart Settings