HP 3PAR Operating System Software User Manual
Page 148
No Communication on the Part of Quorum Witness with Site 1 and Site 2
In a dual-network communication failure resulting in no communication between the quorum witness
and site 1, and between the quorum witness and site 2 (see
):
•
HP 3PAR StoreServ array A and B have both lost connectivity with the quorum witness.
•
Remote-copy links are operational, and the HP 3PAR StoreServ arrays are aware of each
other’s operational state.
•
A failover does not take place:
Host I/O continues to go to source volumes.
◦
◦
Replication of I/O across remote-copy links continues as usual.
Figure 59 No Communication on the Part of Quorum Witness with Site 1 and Site 2
No Communication among Quorum Witness, Site 1, and Site 2
In a triple-network communication failure such that there is no communication among Quorum
Witness, Site 1, and Site 2 (see
):
•
StoreServ A would be unable to update the quorum witness in the context of the failure of the
RC links, and would expect an operational HP 3PAR StoreServ array B (with connectivity to
the quorum witness) to fail over to source. Consequently, HP 3PAR StoreServ array A would
perform a failsafe operation to become a target site, in order to avoid the potential for both
systems to serve host I/O.
•
Similarly, HP 3PAR StoreServ array B, which now has no view of either the quorum witness
or HP 3PAR StoreServ array A, cannot know whether HP 3PAR StoreServ array A is operational,
and therefore remains the target.
•
A failover takes place:
StoreServ A performs a failsafe operation to become the target.
◦
◦
StoreServ B is already, and remains, the target.
◦
Host I/O is stopped.
◦
Replication of I/O across RC links stops.
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HP 3PAR Peer Persistence with Transparent Failover