HP StorageWorks XP Remote Web Console Software - Manual (Page 37)

performed on suspended pairs. While the resync operation for a split pair can be very fast, the resync
operation for a suspended pair takes as long as the initial copy operation.
The storage system automatically suspends a Siz pair when it cannot keep the pair mirrored for any
reason. When the storage system suspends a pair, sense information is generated to notify the host. The
storage system automatically suspends a Siz pair under the following conditions:
• When the storage system detects an error condition related to an update copy operation.
• When the differential bitmap in shared memory is lost (e.g., due to offline microcode exchange).
This applies to SP-pend and V-split pairs only. For duplex, split, resync, or resync-r pairs, the pair
is not suspended but the entire S-VOL (T-VOL for reverse copy) is marked as differential data.
The Suspend Volume Pair dialog box (see section
“ Suspending Hitachi ShadowImage for z/OS Pairs ” on page 85) allows you to suspend Siz
pairs. When a pair is suspended, the pair status changes to suspended. When the resync
operation starts, the pair status changes to resync. The S-VOL remains fully accessible while
suspended and during the resync operation. The re-synchronize Volume Pair dialog box (see section
“ Re-synchronizing Hitachi ShadowImage for z/OS Pairs ” on page 83) allows you to re-synchronize
suspended Siz pairs.
• The PPRC commands do not support the Siz suspend operation. You must use the Siz Remote
Web Console software to suspend Siz pairs.
• The CSUSPEND and PPRCOPY SUSPEND commands execute a Siz split operation instead of a
suspend operation. See Chapter 5 on page 99 for more information on using PPRC commands to
perform Siz operations on the storage system.
Delete Pair Operation
The Siz delete pair operation stops the Siz update copy operations to the T-VOL of the pair and changes
the pair status of both volumes to simplex. A Siz pair can be deleted by the user at any time except
during the quick split operation (i.e., any status except simplex and V-split). After you delete a Siz pair,
the T-VOL is still not available for write operations until the reserve attribute is reset.
The Delete Volume Pair dialog box (see section “
Viewing Past Record of Pair Operations ” on page 89)
allows you to delete Siz pairs. When a Siz pair is deleted, pending update copy operations for the pair
are discarded, and the status of the S-VOL and T-VOL is changed to simplex.
CAUTION:
The T-VOL of a duplex pair may not be identical to its S-VOL, due to the asynchronous Siz update copy
operations. To synchronize the volumes before deleting the pair, you must split the pair first (see section
“ Splitting Hitachi ShadowImage for z/OS Pairs ” on page 78 for instructions).
Hitachi ShadowImage™ for z/OS Options
Siz allows you to set 32 types of options for the Siz operations. By using the Siz options, you may
enhance Siz operations such as the add pair and resync pair operations. The number of available option
types depends upon your storage system settings.
Hitachi ShadowImage for z/OS user guide 37