Even though the communication between the peers of an Edge HA deployment is designed for maximum resiliency, there is a remote possibility of a failure scenario known as split brain. Split brain can occur if the heartbeat communication between the peers fails simultaneously in all aspects; that is, both heartbeat interfaces fail at the same time. If these interfaces are directly connected through cross-over cables then the possibility is extremely remote. But if the heartbeat interfaces are connected through network switches, then depending on the design and topology, split brain might occur.

In a split-brain condition, both Edge appliances act as if the peer has failed. This action can result in both peers being Active Degraded. Because both peers can be simultaneously trying to serve data and also be synchronizing data back through the Core, this action could lead to data integrity issues.

There are ways to recover from this scenario, but the best course of action is to contact Riverbed Support and open a support case. Any recovery process is likely to be different from another so the actual procedure may vary depending on the failure sequence.