HP XP P9000 Continuous Access Synchronous for Mainframe Systems User Guide

10. At the remote or secondary site, start critical host operations, with the previous S-VOLs now
the main volumes.
Checking S-VOL currency with the P-VOL
An S-VOL's currency refers to whether S-VOL data is identical to data in the P-VOL. This is dependent
on your Fence Level setting, which determines whether data is copied to the P-VOL if an error
occurs during an update to the S-VOL.
The following table shows S-VOL currency information, based on pair status and the P-VOL fence
level setting. (For the corresponding RAID Manager status names, see “RAID Manager pair status
names” (page 77).)
Currency of S-VOLFence levelTypeS-VOL status
Not current. The S-VOL does not belong to a Continuous Access
Synchronous Z pair. Even if you have created a Continuous Access
Data Status
Never
--Simplex
Synchronous Z pair using this volume, if the pair status is still Simplex,
you must regard its data as not current with the P-VOL.
Not current. The S-VOL is not synchronized because not all tracks have
been copied from the P-VOL yet. This S-VOL must be initialized (or
copied from the P-VOL at a later time).
Data Status
Never
--Pending
Current. The S-VOL is synchronized with its P-VOL.Data Status--Duplex
* Needs to be analyzed. The S-VOL requires further analysis to
determine its level of currency.
Never
Not current. The S-VOL is not synchronized because not all tracks have
been copied from the P-VOL yet. The S-VOL must be initialized (or
copied from the P-VOL at a later time).
Data Status
Never
Initial copy
failed
Suspended
Suspect. The S-VOL is not synchronized with its P-VOL if any write I/Os
were issued to the P-VOL after the pair was suspended. The pair should
Data Status
Never
P-VOL by
operator
Suspended
be released and restarted using Entire Volume for Initial Copy option.
If you are sure that no data on the P-VOL changed, you can use the
None option.
Current. The S-VOL is synchronized with its P-VOL.DataAll other typesSuspend
Suspect. The S-VOL is not synchronized with its P-VOL if any write I/Os
were issued to the P-VOL after the pair was suspended. Restore the
Status Never
consistency of the S-VOL and update it, if required. The time of
suspension indicated on the Last Update Time field of the Detailed
Information dialog box (MCU SVP time) will help to determine the last
time the S-VOL was updated.
For pairs with a P-VOL fence level setting of Never, further analysis is required to determine the S-VOL currency. This can be
determined by using sense information transferred via host failover, or by comparing the contents of the S-VOL with other files
that are confirmed to be current (for example, database log files). The S-VOLs should be recovered using the files that are
confirmed to be current.
Actual data recovery must be done using recovery point data in the database redo log.
Transferring operations back to the primary site
When host operations are running at the remote or secondary site, the primary site should be
restored and operations transferred back.
In the following procedure, you will establish Continuous Access Synchronous Z pairs at the remote
or secondary site, with data flow moving from the remote or secondary site to the local. After the
pairs are synchronized and in Duplex status, they will be released, then new pairs will be created
at the local site with data flow moving from local to remote, as originally set up.
To transfer operations to the primary site:
106 Disaster recovery