Edge high availability enables you to configure two appliances so that either one can fail without disrupting the service of any of the LUNs provided by the Core. To enable Edge high availability, you configure a pair of Edges: one as an active peer and the other as a standby peer. The active Edge in the pair connects to the Core and serves storage data. The active peer contains the authoritative copy of the blockstore and configuration data. The standby Edge is passive and does not service client requests but is ready to take over from the active peer immediately.

As the system writes new data to the active peer, it reflects the data to the standby peer, which stores a copy of the data in its local blockstore. The two appliances maintain a heartbeat protocol between them, so that if the active peer goes down, the standby peer can take over servicing the LUNs. If the standby peer goes down, the active peer continues servicing the LUNs, after raising a high availability alarm indicating that the system is now in a degraded state.