HP XP P9500 Storage - Manual (Page 66)

Description Volume applies
to PSUS type
without power for more than 48 hours (that is, power failure and fully
discharged backup batteries).
The pair was suspended before the initial copy operation was complete. The
data on the S-VOL is not identical to the data on the P-VOL. P-VOL
S-VOL
Initial copy failed
System behavior
Note the following behaviors for suspended pairs:
•
The primary system stops performing update operations to the S-VOL. It may or may not
continue accepting write I/Os to the P-VOL depending on the P-VOL fence level setting.
•
If an update fails, the primary system maintains exact synchronization by reporting a unit
check and de-committing the P-VOL update. This ensures that both the host system and
application program regard the write operation to the P-VOL as failed.
•
If the primary system accepts subsequent write I/Os for a suspended P-VOL, the system records
the updated data in the P-VOL tracks as differential data. When a suspended pair is
resynchronized, the primary system copies the out of sync P-VOL tracks to the S-VOL as
differential data.
Monitoring copy operations, I/O statistics
You can monitor copy operations data and I/O statistics in the Usage Monitor window. This topic
shows you how to do this, and also how to perform the following tasks:
•
Selecting data for the usage monitor graph (page 67)
•
Resizing the usage monitor graph, saving data (page 68)
For information on how to start and stop monitoring in Performance Monitor, see the HP XP P9000
Performance for Open and Mainframe Systems User Guide.
To monitor copy operations, in the Remote Web Console, click Actions > Remote Copy > Continuous
Access Synchronous > Usage Monitor.
66 Monitoring and maintenance