HP XP7 Storage - Manual (Page 156)

The MU number indicates that the pair is a Business Copy pair and not a Continuous Access
Synchronous pair. Once the correspondence between the paired logical volumes has been defined
in the HORCM_DEV section of the configuration file, you can use the configuration file to group
the paired volumes into volume groups that can be managed by the host operating system's LVM
(logical volume manager).
The host's LVM allows you to manage the Continuous Access Synchronous/Business Copy volumes
as individual volumes or by volume group. Continuous Access Synchronous/Business Copy
commands can specify individual logical volumes or group names. For LUSE volumes, you must
enter commands for each volume (LDEV) within the expanded LU. If you define volume groups and
you want to issue commands to those volume groups, you must register the volume groups in the
configuration file. For further information about the server LVM, see the user documentation for
your corresponding operating system.
Continuous Access Synchronous/Business Copy/Continuous Access Journal pair
status
Each Continuous Access Synchronous pair consists of one P-VOL and one S-VOL, and each Business
Copy pair consists of one P-VOL and up to nine S-VOLs when the cascade function is used.
Table 30 (page 156) lists and describes the Continuous Access Synchronous and Business Copy
pair status terms. Table 31 (page 157) lists and describes the Continuous Access Journal pair status
terms. The P-VOL controls the pair status for the primary and secondary volumes. The major pair
statuses are SMPL, PAIR, PSUS/PSUE, and COPY/RCPY. Read and write requests from the host
are accepted or rejected depending on the pair status of the volume.
The pair status can change when a RAID Manager command is executed. The validity of the
specified operation is checked according to the status of the volume (primary volume).
•
Table 32 (page 158) shows the relationship between pair status and Continuous Access
Synchronous/Continuous Access Journal command acceptance.
•
Table 33 (page 158) shows the relationship between pair status and Business Copy command
acceptance.
•
Table 34 (page 160) shows the relationship between pair status and Snapshot command
acceptance.
For detalis on pair status of Continuous Access Synchronous Z, Business Copy Z, and Continuous
Access Journal Z, see
“Pair operations with mainframe volumes” (page 88) .
Table 30 Continuous Access Synchronous and Business Copy pair status
Secondary Primary Business Copy Pair Status Continuous Access Synchronous Pair
Status Status
R/W enabled R/W enabled Unpaired volume Unpaired volume SMPL
R enabled R/W enabled Paired volume. Initial copy is complete.
Updates are processed asynchronously. Paired volume. Initial copy is complete.
Updates are processed synchronously or
asynchronously. PAIR
R enabled R/W enabled In paired state, but initial copy, pairsplit,
or resync operation is not complete. In paired state, but initial copy, pairsplit,
or resync operation is not complete. COPY
Includes COPY(PD), COPY(SP), and
COPY(RS) status. Includes COPY(PD), COPY(SP), and
COPY(RS) status.
R enabled R enabled In paired state, but reverse resync
operation is not complete. Includes
COPY(RS-R) status. Not used for Continuous Access
Synchronous RCPY
R/W enabled
when using R/W enabled In paired state, but updates to the S-VOL
data are suspended due to user-requested In paired state, but updates to the S-VOL
data are suspended due to user-requested PSUS
(split)
write enable
pairsplit option pairsplit. The RAID storage system keeps
track of P-VOL and S-VOL updates while
the pair is split. pairsplit. The RAID storage system keeps
track of P-VOL and S-VOL updates while
the pair is split. SSUS
(split)
156 Data replication operations with RAID Manager