About the high availability appliance cluster

HPE OneView achieves high availability through an appliance cluster that comprises two appliances. The appliances are defined by their role:

Role

Function

active

Currently hosts the services for the appliance cluster.

standby

Ready to become the active appliance in case the active appliance becomes unavailable. The standby appliance becomes active when:

  • The active appliance is physically removed or loses power.

  • The connection between the cluster members is broken or interrupted.

  • The active appliance experiences repeated software faults, causing it to reboot itself.

unused

Ready to become a standby appliance if it has a compatible firmware version and the previous standby appliance is no longer configured for standby or was removed from the enclosure.

The standby appliance monitors the active appliance and assumes control when contact is lost.

Consider two cluster members A and B:

  • The standby appliance (B) detects that it can no longer communicate with the active appliance (A).

  • Cluster member B causes A to reboot.

  • Cluster member B assumes control of operations as the active appliance.

  • Cluster member A becomes the standby appliance.

  • The appliance cluster becomes highly available again.

In addition, you can activate the standby appliance manually to cause the cluster members to swap roles.