HP XP Business Copy Software - Manual (Page 12)

Cascade pairs
The BC cascade function adds a second layer of pairs onto the first layer of original BC pairs. Use
these two layers of pairs (L1 and L2) to create and maintain up to nine copies of one original BC
primary volume (P-VOL). See
Cascade function for further information on the cascade function.
BC software on the Command View XP management station
When installed on the Command View XP management station, the BC software displays BC information
and performs BC operations. The Command View XP management station can be attached to multiple
disk arrays. The Command View XP management station acquires status from and issues commands
to BC P-VOLs and S-VOLs.
BC requirements for the array
BC operations provide local copies of UNIX/PC server volumes (LUs) on the disk array. The following
table describes the operational requirements for BC.
Table 1 BC operational requirements for the array
Requirement Parameter
Logical devices (LDEVs): OPEN-x (such as OPEN-3, OPEN-9, OPEN-E, and OPEN-V),
including CVS and LUSE volumes. Devices must be installed and configured. The
P-VOL and S-VOL must be the same type (for example, OPEN-3 to OPEN-3 is allowed,
OPEN-3 to OPEN-9 is not allowed).
A custom size P-VOL must be paired with S-VOLs of the same type and capacity. A
LUSE P-VOL must be paired with S-VOLs of the same size and structure. For example,
if a LUSE P-VOL is connected to volumes of 1GB, 2GB, and 3GB in this order, you
must specify the LUSE volume that has exactly the same size and connection order as
the S-VOL.
BC does not support multiplatform devices (for example, 3390-3A, -3B, -3C).
For information about using Snapshot XP pair volumes as Business Copy XP volumes,
see Snapshot XP User’s Guide.
Snapshot XP pairs, virtual volumes, and pool volumes cannot be specified as P-VOLs
or S-VOLs.
Journal volumes for HP StorageWorks Continuous Access XP Journal cannot be
specified as P-VOLs or S-VOLs.
Volumes that form a Flex Copy XP pair cannot be specified as P-VOLs. A Flex Copy
XP P-VOL can be specified as a Business Copy XP S-VOL under certain conditions.
See the HP StorageWorks Flex Copy XP user guide for more information.
BC operations can be performed with External Storage XP operations to create pairs
that use the external volumes as BC S-VOLs (or mirroring volumes) under the same
conditions applied to the volumes in the local disk array. See the HP StorageWorks
External Storage XP user guide for more information.
Pair objects
Maximum of three copies (S-VOLs) per primary volume (P-VOL). Maximum of one
P-VOL per S-VOL (P-VOLs cannot share an S-VOL).
An additional six copies can be created by using the BC cascade function.
Number of copies
Business Copy XP (BC) for the Array 12