Operations Permitted For L1, L2 Pairs - HP StorageWorks P9000 User Manual

Table 5 Pair status definitions (continued)
Status
COPY(SP)
PSUS(SP)
PSUS
COPY(RS)
COPY(RS R)
PSUE
* Starting time of the copy depends on the numbers of pairs and the system environment.

Operations permitted for L1, L2 pairs

When you have cascaded pairs, the operations that may be performed depend on pair status on
both layers.
Any operation, of course, requires that the pair's status is correct for that operation (see
definitions" (page
For L1 operations, the status of the L2 pair.
For L2 operations, the status of the L1 pair.
Supported read/write on L1 and L2 S-VOLs.
Operations that are supported for these pair types and statuses are shown in the following tables.
Table 6 Supported L1 pair operations for related L2 status
L2 Pair Status
COPY(PD)
PAIR
COPY(SP)
PSUS(SP)
PSUS
COPY(RS)
COPY(RS-R)
Description
The pairsplit operation in the steady split mode has begun. Any remaining
differential data is copied to the S-VOL. When these updates are complete, the
pair is split. The split S-VOL is identical to the P-VOL at the time of the split.
The pairsplit operation in the quick split mode has begun. P-VOL differential data
is copied to the S-VOL in the background. Pairs in PSUS(SP) status cannot be
deleted.
The pair is split. The system stops performing update copy operations. Write
I/Os are accepted for S-VOLs. The system keeps track of updates to split P-VOLs
and S-VOLs, so that the pair can be resynchronized quickly.
The pairresync operation has begun. The system does not accept write I/Os for
COPY(RS) S-VOLs. When a split pair is resynchronized in normal mode, the
system copies only P-VOL differential data to the S-VOL. When a PSUE
(suspended) pair is resynchronized, the system copies the entire P-VOL to the
S-VOL. No update copy operations are performed during the pairresync
operation.
The reverse pairresync operation has begun. The system does not accept write
I/Os for COPY(RS R) S-VOLs. The system copies only S-VOL differential data to
the P-VOL. No update copy operations are performed during the reverse or
quick restore pairresync operation.
The pair is suspended by the system. The system continues accepting read and
write I/Os to the P-VOL. Update copy operations are stopped to a S-VOL. The
system marks the entire P-VOL track map as difference data, meaning that the
entire P-VOL is copied to the S-VOL when the PSUE pair is resynchronized.
36)). In addition, an operation depends on the following:
L1 Pair Operations
Paircreate Pairsplit
Ok* Ok
Ok* Ok
NO* NO*
NO* NO*
Ok* Ok
Ok* Ok
NO* NO
Pairresync Pairsplit-E
Ok Ok
Ok Ok
NO Ok
NO Ok
Ok Ok
Ok Ok
-- --
S-VOL Access
Read only
Read and write.
The S-VOL can be
mounted.
Read and write.
The S-VOL can be
mounted.
Read only
Read only
Read only
"Pair status
Pairsplit-S
Ok
Ok
Ok
Ok
Ok
Ok
--
Monitoring the system 37