Veritas Storage Foundation 5.1 SP1: Storage and Availability Management for Oracle (5900-1504, April 2011)

The following sample procedure is for existing volumes without existing snapshot

plexes or associated snapshot volumes. In this procedure, volume_name is the

name of either a volume or a volume set.

Note: You must be logged in as superuser (root) to issue the commands in the

following procedure.

To create a snapshot mirror of a volume or volume set

To prepare the volume for being snapshot, use the vxsnap prepare command:

# vxsnap -g diskgroup prepare volume \

alloc="storage_attribute ..."

The vxsnap prepare command automatically creates a DCO and DCO volumes

and associates them with the volume, and enables Persistent FastResync on

the volume. Persistent FastResync is also set automatically on any snapshots

that are generated from a volume on which this feature is enabled.

For enabling persistent FastResync on a volume in VxVM 4.1 or 5.0, either

from the command line or from within a script, use the vxsnap prepare

command as described above.

To verify that FastResync is enabled on the volume, use the vxprint command:

# vxprint -g diskgroup -F%fastresync volume_name

This returns on if FastResync is on. Otherwise, it returns off.

To verify that a DCO and DCO log volume are attached to the volume, use the

vxprint command:

# vxprint -g diskgroup -F%hasdcolog volume_name

This returns on if a DCO and DCO log volume are attached to the volume.

Otherwise, it returns off.

135Using Database FlashSnap for backup and off-host processing

Preparing hosts and storage for Database FlashSnap