After a failover command is issued, a failback command
is issued to restart replication from volumes h2 to h3.
Procedure
Issue a PPRC failback command to the h2 to h3 volumes.
As part of command processing, out-of-sync data from volume
h3 is merged with volume h2.
TSO/E command
DS CLI command
ANTRQST API command
ICKDSF command
CESTPAIR ACTION(FAILBACK)
failbackpprc
REQUEST=PESTPAIR ACTION=FAILBACK
PPRCOPY ESTPAIR FAILBACK
When the merging of data completes, the h2 and h3 volumes
are resynchronized and allowed to reach a full-duplex state. (Recording
mechanisms on volumes h2 and h3 volumes track out-of-sync data to
allow resynchronization to be incremental, without requiring a full
copy of data.)
The Metro Mirror volume pair is no longer
in a Multi-Target Incremental Resync relationship. Figure 1 shows the configuration
after a failback from the h2 to h3 volumes.
Figure 1. Configuration after a failback from
the h2 to h3 volumes
