HP XP Racks - Manual (Page 43)

5 System maintenance
To ensure that the ESAM system function properly and is able to provide robust and reliable
high-availability protection for host applications, it is essential for you to be able to perform ESAM
system maintenance tasks.
Applications used to perform maintenance tasks
All of the typical maintenance tasks can be completed using RWC or RAID Manager.
Required Remote Web Console settings
You must be in Modify Mode in RWC.
Related documentation
For more information about other system maintenance tasks, see the HP XP P9000 Continuous
Access Synchronous User Guide.
The different types of maintenance tasks
The following tasks can be performed.
•
“Switching paths using multipath software ” (page 43)
•
“Discontinuing ESAM operations ” (page 43)
•
“Quorum disk ID deletion ” (page 44)
•
“Recovery of accidently deleted quorum disks” (page 45)
•
“Planned outages for system components” (page 46)
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 updates 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.
Applications used to perform maintenance tasks 43