Recovering from primary volume failure on the rcu – HP XP Racks User Manual
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5.
On the primary storage system, make sure that no other failures exist and that it is ready to
accept host I/O.
6.
On the secondary storage system, create a Continuous Access Synchronous pair from the
original S-VOL to the P-VOL. The data flow is from the secondary to primary storage system.
7.
Continue by changing the Continuous Access Synchronous pair to a ESAM pair (below) or
recreating the ESAM pair (next step).
If changing the Continuous Access Synchronous pair to a ESAM pair, complete this step on
the primary storage system.
1.
On the primary system, use RAID Manager to run the horctakeover command on the new
TrueCopy S-VOL. This reverses the relationship and the copy flow from S-VOL to P-VOL.
2.
On the primary system, use RWC to split the TrueCopy pair.
3.
On the primary system, perform the RWC pair resync operation to change the TrueCopy
pair to a HAM pair. See
“Changing Continuous Access Synchronous pairs to ESAM pairs
.
8.
If recreating the ESAM pair:
1.
Using either RAID Manager or RWC, on the secondary storage system, release the
Continuous Access Synchronous pair (for RAID Manager, use the pairsplit -S
command.
2.
On the primary storage system, create the ESAM pair.
9.
On both systems, in RWC, make sure that Type shows ESAM.
10. Using multipath software, vary the owner path online.
11. Restart I/O.
Recovering from primary volume failure on the RCU
This failure occurs after automatic system failover switches host I/O to the primary volume on the
RCU due to a failure of the primary volume on the primary storage system. Because both systems
have volume failures, all host I/O stops. Recovering the volume from this failure involves releasing
the pair, clearing the failure (and any failures on the primary storage system), recreating the pair,
restoring the original relationship of the volumes, and restoring normal host I/O.
NOTE:
If the failed volume is an external volume, contact the HP Support Center for assistance
clearing the failure.
You use multipath software and RWC to complete this task.
1.
Make sure that I/O is stopped.
2.
Using multipath software, vary the non-owner path offline.
3.
On the secondary storage system, release the ESAM pair by running the Pairsplit-S
command on the P-VOL.
4.
Clear the failure in the secondary storage system P-VOL.
5.
If using RAID Manager, on the primary storage system, run the paircreate command to
create the ESAM pair.
6.
If using RWC, on the primary storage system use a Paircreate (ESAM) window to create the
ESAM pair.
7.
Clear any failures on the primary storage system so that it can accept I/O.
8.
On the primary storage system, create the pair (Paircreate(ESAM)).
9.
On both systems, make sure that Type shows ESAM.
10. Using multipath software, vary the owner and non-owner paths online.
11. Restart host I/O.
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Disaster recovery