HP StorageWorks XP Remote Web Console Software - Manual (Page 32)

32 Continuous Access XP Journal
When you split a Continuous Access XP Journal pair, the primary and secondary disk arrays ensure
synchronization by completing or discarding pending update copy operations according to the
user-specified pending update option (purge/flush). The primary and secondary disk arrays keep track of
journal data discarded during the pairsplit operation. After the pair status changes to PSUS, the primary
disk array stops performing journal obtain operations for the pair, continues accepting write I/Os for the
split Continuous Access XP Journal primary data volume, and keeps track of primary data volume tracks
that are updated while the pair status is split. If you enabled the secondary data volume write option when
you split the pair, the secondary disk array keeps track of the secondary volume tracks that are updated
while the pair is split. When the pair is resumed (pairresync), the secondary disk array sends the
secondary data volume’s track bitmap to the primary disk array, and the primary disk array merges the
primary and secondary data volume bitmaps to determine which tracks are out-of-sync.
A split (or suspended) Continuous Access XP Journal secondary data volume has an additional status
called the consistency status. The consistency status is displayed only at the secondary disk array and
indicates the update sequence consistency of the secondary data volume with respect to the other
secondary data volume in the same group. Table 6 describes consistency statuses for split or suspended
Continuous Access XP Journal secondary data volumes (the consistency status is displayed only at the
secondary disk array).
Table 5 Continuous Access XP Journal split types (PSUS)
Type Applies to Description
PSUS, P-VOL by
Operator
Primary data volume The secondary data volume’s split type is PSUS-by MCU.
PSUS, S-VOL by
Operator
Primary data volume,
Secondary data volume
You split the pair from the primary or secondary disk array
using the secondary data volume option.
PSUS, by MCU Secondary data volume The secondary disk array received a request from the
primary disk array to split the pair. The primary data
volume’s split type is PSUS-P-VOL by Operator or
PSUS-S-VOL by Operator.
PSUS, by RCU Primary data volume,
Secondary data volume
The primary disk array detected an error condition at the
secondary disk array that caused the primary disk array to
suspend the Continuous Access XP Journal data volume pair.
The secondary data volume suspend type is PSUE-S-VOL
Failure.
PSUS, Pairsplit-S
to RCU
Primary data volume The primary disk array detected that the secondary data
volume’s status changed to SMPL because you deleted the
pair (pairsplit-S) from the secondary disk array. The pair
cannot be resumed because the secondary data volume
does not have the PSUS/PSUE status.
PSUS, JNL Cache
Overflow
Primary data volume,
Secondary data volume
The data volume pair was suspended because it was highly
likely that journal data would overflow.
NOTE: RAID Manager displays this split type as
PFUS.