Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

To set up a replica database to be used for decision support on an OHP host
1
If you have not already done so, prepare the OHP host to use the snapshot
volume that contains the copy of the database tables. Set up any new database
logs and configuration files that are required to initialize the database.
See “About preparing a replica Oracle database” on page 525.
2
On the primary host, use the following command to make a full-sized
snapshot, snapvol, of the tablespace volume by breaking off plexes from the
original volume:
# vxsnap -g volumedg make \
source=volume/newvol=snapvol/nmirror=N
The nmirror attribute specifies the number of mirrors, N, in the snapshot
volume.
If the volume does not have any available plexes, or its layout does not support
plex break-off, prepare an empty volume for the snapshot.
See “Creating a volume for use as a full-sized instant snapshot” on page 150.
Then use the following command to create the snapshot:
# vxsnap -g volumedg make source=volume/snapvol=snapvol
If a database spans more than one volume, specify all the volumes and their
snapshot volumes as separate tuples on the same line.
For example:
# vxsnap -g dbasedg make source=vol1/snapvol=svol1 \
source=vol2/snapvol=svol2 source=vol3/snapvol=svol3
Note: This step sets up the snapshot volumes, and starts tracking changes to
the original volumes.
When you are ready to create the replica database, proceed to step 3.
3
If the volumes to be backed up contain database tables in file systems, suspend
updates to the volumes:
■ DB2 provides the write suspend command to temporarily suspend I/O
activity for a database. As the DB2 database administrator, use a script
such as the example script.
See “Script to suspend I/O for a DB2 database” on page 516.
Decision support
Creating an off-host replica database
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