Automatic failover for data recovery occurs if the source replication server is unavailable because of a disaster or a system outage.
During normal operations, when the Tivoli® Storage Manager V7.1 client logs in to a source replication server, it receives connection information for the target failover server. The client node stores the failover connection information in the client options file. During client restore operations, the Tivoli Storage Manager server automatically changes clients to the target replication server and back again. Only one failover server can exist per node at any time. The server information is stored in the options file. The failover server can be modified only if the default replication server is modified and another replication is completed for the node.
To use automatic failover for replicated client nodes, the source replication server, the target replication server, and the client must be at the v7.1 level or later. If any of the servers are at an earlier level, automatic failover is disabled and you must rely on manual failover.
If the client cannot connect to the source replication server, it uses the failover connection information and attempts to log on to the target failover server. The client logs on to the target replication server and is allowed only to recover data. The client cannot store data during failover processing.
When a new client operation is started, the client attempts to connect to the source replication server. The client resumes operations on the source server if the source replication server is available.
When you configure a node for replication by using the REGISTER NODE command or the UPDATE NODE command, the failover server is not specified.