Viewing quorum disks, Maintenance tasks, Switching paths using multipath software – HP XP P9500 Storage User Manual
Page 40: Discontinuing esam operations, Viewing quorum disks maintenance tasks
Viewing quorum disks
Use the Quorum Disk Operation window to find a quorum disk's LDEV number, or to find which
quorum disk ID is assigned to the quorum disk.
To display the Quorum Disk Operation window, click Actions
→Remote Copy→Continuous Access
Synchronous
→Quorum Disk Operation.
Maintenance tasks
The following sections describe maintenance procedures using Remote Web Console. You must
be in Modify Mode in Remote Web Console.
Switching paths using multipath software
Before switching paths using multipath software, make sure that P-VOL and S-VOL status is PAIR.
If the path is switched while the ESAM pair is not in the PAIR status, I/O operations could be
suspended or the host might read older data.
Vary the paths as follows:
•
When both owner and non-owner paths are online, vary the owner path offline.
•
When the owner path is offline and non-owner path is online, vary the owner path online.
CAUTION:
When the ESAM pair is in the PAIR status, if you vary the owner path online, non-owner
paths on RCU may be changed to offline. Since no failure actually occurred in these paths, you
should restore the status of the ESAM pair to PAIR, and then vary the non-owner paths online.
I/O scheduled before making the owner paths online with the multipath software is issued to
non-owner paths. According to circumstances, I/O scheduled after making owner paths online
might be issued prior to I/O scheduled before making owner paths online. In this case, the check
condition on I/O which is issued to non-owner paths may report to the host because the RCU
ESAM pair is in the PSUS status and the MCU ESAM pair is in the SSWS status. I/O which is
reported on the check condition are reissued to the owner path, and then ended normally.
Non-owner paths which are reported on the check condition become offline due to failures.
Discontinuing ESAM operations
You can discontinue ESAM operations at any time. While an ESAM pair uses the quorum disk,
you cannot delete the external volume mapping.
Procedure 17 To discontinue all operations:
1.
Using multipath software, vary the non-owner path to offline using the multipath software.
2.
Release all ESAM pairs from the primary system. See
3.
From the primary and secondary systems, verify that the pair status for all volumes is SMPL.
If the status does not change to SMPL due to a failure of the remote copy connections, release
all ESAM pairs from the secondary system.
4.
From the primary and secondary systems, delete all quorum disk IDs. See
(below). The quorum disk becomes a normal external volume.
5.
From the primary and secondary systems, disconnect the quorum disk. In the External Storage
window, select the quorum disk and specify the Disconnect External Volumes command. For
details about the External Storage window, see HP P9000 External Storage for Open and
Mainframe Systems User Guide.
6.
From the primary and secondary systems, delete the mapping of the quorum disk. In the
External Storage window, select the quorum disk and specify the Delete External Volumes
command.
7.
Remove the cables between the host and secondary system, between the primary and secondary
systems and the quorum disk.
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Monitoring and maintenance