HP StorageWorks HSG80 ACS Solution Software V8.8 for IBM AIX Installation and Configuration Guide (AA-RV1HA-TE, March 2005)

Backing Up, Cloning, and Moving Data
183HSG80 ACS Solution Software V8.8 for IBM AIX Installation and Configuration Guide
Clone and Snapshot and AIX Environment
The Clone and Snapshot functions permit an HP StorageWorks storage system to
make copies of its internal drives. Once these copies become available,
applications such as backup can be implemented on the copies, and not affect
production work with the original drives.
In AIX, volume groups can be copied in this manner, however AIX does not
permit the existence of two or more exact volume group copies in same system
environment. The following describes the steps necessary to make the appropriate
copies (Clone or Snapshot) of AIX volume groups and to import these copies into
the same environment as the originals.
The basic system requirements are an AIX RS/6000 system configured with an
HSG80 storage system with enough unassigned drives to make the copy.
Volume group copies can be imported through the use of the AIX command
recreatevg. Additionally, in order to use the Snapshot function, the HSG80
controller must be loaded with “S” type firmware.
Note: In the case of more than one candidate volume groups on the same system
targeted for copy, this procedure should be executed for each candidate one at a
time. The volume group can remain imported and their respective logical volumes
remain mounted during a Clone or Snapshot, however, writes to the volume group
can break the data consistency while a Clone operation is active. When cloning is
complete, then volume group access can resume with the original without affecting the
copy. This is not the case for Snapshot, however, and as such you can continue
volume group access while also accessing the Snapshot volume group.
In the solution software, there are tools to help create, list, delete Snapshots out on
the HSG80 from the operating system. There are also tools in this kit to
automatically redefine a volume group of a Snapshot or Clone so that it does not
appear to the operating system to be the same volume group as the original.
There are two sections that follow. The first describes the Snapshot tools that are
included with the solution software. The second is a description of how to
manually create a Snapshot and redefine the volume group for use with AIX.