Failback without recovery on host b, P-vol, S-vol – HP XP RAID Manager Software User Manual

Page 345: S-vol p-vol, P-vol s-vol

HA Failover and failback

345

Failback without recovery on Host B

The following procedure for recovery is necessary if, after host and
ESCON/FC link recovery, you stop the application without executing the
pairresync –swaps

command on Host B and restart the application on the

Host A. At that time, the pairvolchk command on Host A will return
PVOL_PSUE and SVOL_PSUS as the state combination.

pairresync –swapp

This is used to swap the P-VOL/S-VOL designations during the P-VOL
suspend state. The new S-VOL is based on the data of the new P-VOL. The
target volume of the local host must have been the P-VOL, which was
probably out of date.

Delta COPY

Æ PAIR

P-VOL

Host C

Host A

Host B

PAIR

PSUE

PAIR
PAIR
PAIR

SSUS
SSUS
SSUS
SSUS
SSUS

S-VOL

Host C

Host A

Host B

COPY
COPY
COPY
COPY
COPY

pairresync

-swapp

on Host A

S-VOL

P-VOL

Host C

Host A

Host B

PAIR
PAIR
PAIR
PAIR
PAIR

S-VOL

P-VOL

After PAIR

horctakeover

Host C

Host A

Host B

PAIR
PAIR
PAIR
PAIR
PAIR

P-VOL

S-VOL