VERITAS Volume Manager 3.5 Administrator's Guide (September 2004)

Conﬁguring Off-Host Processing

Implementing Off-Host Processing Solutions

Chapter 11376

• “Implementing Decision Support” on page 380

These applications use the Persistent FastResync and disk group move,

split and join features of VxVM in conjunction with volume snapshots.

Implementing Online Backup

This section describes a procedure for implementing off-host online

backup for a volume in a private disk group. The intention is to present

an outline of how to set up a regular backup cycle by combining the

Persistent FastResync and disk group split and join features of VxVM. It

is beyond the scope of this guide to describe how to conﬁgure a database

to use this procedure, or how to perform the backup itself.

To back up a volume in a private disk group, use the following procedure.

Step 1. Use the following command on the primary host to see if the volume is

associated with a data change object (DCO) and DCO volume that allow

Persistent FastResync to be used with the volume:

# vxprint -g volumedg -F%hasdcolog

volume

This command returns on if there is a DCO and DCO volume; otherwise,

it returns off.

If the volume is not associated with a DCO object and DCO volume,

follow the procedure described in “Adding a DCO and DCO Volume” on

page 263.

Step 2. Use the following command on the primary host to check whether

FastResync is enabled on a volume:

# vxprint -g

volumedg

-F%fastresync

volume

This command returns on if FastResync is enabled; otherwise, it returns

off.

If Persistent FastResync is disabled, enable it using the following

command on the primary host:

# vxvol -g volumedg set fastresync=on

volume