Quorum Witness and automatic transparent failover (ATF)

Quorum Witness is required for automatic transparent failover on a Peer Persistence configuration. The storage systems in a Peer Persistence configuration audit Quorum Witness as an alternative path to the Remote Copy links to determine the operational status of their partner storage system. The storage systems differentiate between a Remote Copy link failure and a storage system failure.
  • Are the two storage systems active, but not communicating because of a Remote Copy link failure? Quorum Witness is still receiving updates from both of the systems. Therefore, no failover is required.

  • Has one of the storage systems failed? Quorum Witness is not receiving updates from the failed system. The active system cannot see the failed system through the Remote Copy link. The active system knows that updates are not being received. A failover is required and occurs automatically.