HP Storage Mirroring Software - Manual (Page 20)

Storage Mirroring Recover overview Page 19 of 677
Failure monitoring and failover
Failover is the process in which a target stands in for a failed source. As a result, user
and application requests that are directed to the failed source are routed to the target.
Storage Mirroring Recover monitors the source status by tracking network requests and
responses exchanged between the source and target. When a monitored source misses
a user-defined number of requests, Storage Mirroring Recover assumes that the server
has failed. Storage Mirroring Recover then prompts the network administrator to initiate
failover, or, if configured, it occurs automatically.
The failover target assumes the network identity of the failed source. When the target
assumes the identity of the source, user and application requests destined for the source
server or its IP address(es) are routed to the target.
When partnered with the Storage Mirroring Recover data replication capabilities, failover
routes user and application requests with minimal disruption and little or no data loss. In
some cases, failover may be used without data replication to ensure high availability on
a server that only provides processing services, such as a web server.