HP StorageWorks XP24000 Continuous Access Journal Software User and Reference Guide, v01 (T5278-96001, June 2007)

S1 to S4: Sequence number
(1): The journal data arrived.
(0): The journal data has not arrived yet.
S1
Receiving
journal data
Selecting
journal data
Setting
journal data
Formal
j
ournal
data
Data
S4 (1) S3 (1)
S2 (0)
S1 (1)
Gr
p
=
n
Gr
p
=
n
Figure 6 Sel ectin g and Settlin g Journals at the Secondary Storage System
The secondary storage system settles and restores the journal data to the secondar y data volume
as
follows:
• Journaldatastoredinthe cache
The journal data is copied to the corresponding cached track and promoted to formal data.
• Journal data stored in the restore journal volume
The journal data is read from the restore journal volume to cache. The journal data that is read
to
cache is co pied to the existing cache track and promoted to formal data. After that, the
space for the restore journal volume is released.
Pair Status
Continuous Access Journal displays the p air status for each data volume of the specified CU Image (CUI)
in the
connected storage system. Table 4 on page 33 lists and describes the Continuous Access Journal
data volume pair statuses. The primary storage system maintains the status of the primary da ta volume
and can change the pair status of the primary data volume and secondar y data volume. The secondary
storage system maintains the status of the secondary data volume and can change the pair status of
the
primary data volume and secondar y d ata volume, but not the primary data volume. The primary
storage system will detect when the secondary storage system changes the secondar y data volume
status (if the path status is normal) and will change the primary data volume status accordingly. You
can display detailed pair status information at the Remote Web Console remote console computer
(Continuous Access Journal Detailed Information window) or at the UNIX/PC server host (R AID Manager
Pairdisplay command) .
A volume which is not assigned to a Continuous Access Journal data volume pair has the status SMPL.
When a
Continuous Access Journal data volume pair is started, the primary storage system changes the
status of the primary data volume and secondary data volume to COPY. When the initial copy operation
is
complete, the primary storage system changes the status of both data volumes to PAIR. When a pair is
suspended due to an error condition, the primary storage system changes the primary data volume a nd
secondary data volume status to PSUE (if the path status is normal) . When a Continuous Access Journal
pair is split by the user (pairsplit-r), the primar y storage system or secondar y storage system changes the
status of the primary data volume and secondary data volume to PSUS (if the path status is normal).
When a
pair is split from the secondary storage system, the secondary storage system changes the
32
About
Continuous Access Journal Operations