Veritas Storage Foundation Intelligent Storage Provisioning 5.0 Solutions Guide, HP-UX 11i v3, First Edition, May 2008

30 Off-host processing solutions
Implementing off-host processing solutions
13 On the primary host, reattach the snapshot volume to its original volume
using the following command:
# vxsnap -g snapvoldg reattach snapvol source= vol \
sourcedg=
volumedg
For example, to reattach the snapshot volumes svol1, svol2 and svol3:
# vxsnap -g sdg reattach svol1 \
source=vol1 sourcedg=dbasedg \
svol2 source=vol2 sourcedg=dbasedg \
svol3 source=vol3 sourcedg=dbasedg
You can use the vxsnap snapwait command to wait for synchronization of
the linked snapshot volume to complete:
# vxsnap -g volumedg snapwait volume mirvol= snapvol
Repeat step 3 through step 13 each time that you need to back up the volume.
Implementing decision support
This section describes a procedure for implementing off-host decision support
for a volume in a private disk group. The intention is to present an outline of
how to set up a replica database by combining the Persistent FastResync and
linked break-off snapshot features of VxVM. It is beyond the scope of this guide
to describe how to configure a database to use this procedure.
To set up a replica database using the table files that are configured within a
volume in a private disk group
1 Prepare the OHP host to receive the snapshot volume that contains the copy
of the database tables. This may involve setting up private volumes to
contain any redo logs, and configuring any files that are used to initialize
the database.
2 On the primary host, create a new volume, snapvol, in a separate disk group,
snapvoldg, for use as the snapshot volume. This volume must be the same
size as the original volume, but it can differ in its layout and other
characteristics, such as the quality of storage. It is recommended that the
snapshot disk group contains storage that is dedicated to off-host
processing.
3 On the primary host, link the snapshot volume in the snapshot disk group to
the data volume:
# vxsnap -g volumedg -b addmir volume mirvol= snapvol \
mirdg=
snapvoldg
You can use the vxsnap snapwait command to wait for synchronization of a
linked snapshot volume to complete:
# vxsnap -g volumedg snapwait volume mirvol= snapvol \
mirdg=
snapvoldg