VERITAS FlashSnap Point-In-Time-Copy Solutions Administrator's Guide

Chapter 4, Off-Host Cluster File System Backup

Mounting a File System for Shared Access

To mount a VxFS file system for shared access, use the following command on each cluster node

where required:

# mount -F vxfs -o cluster /dev/vx/dsk/diskgroup/volume mount_point

For example, to mount the volume cfs_vol in the disk group exampledg for shared access on

the mount point, /mnt_pnt:

# mount -F vxfs -o cluster /dev/vx/dsk/exampledg/cfs_vol /mnt_pnt

Using Off-Host Processing to Back Up Cluster File Systems

Note It is assumed that you have already prepared the volumes containing the file systems that are

to be backed up as described in “Setting up Volumes for Instant Snapshots” on page 17.

To back up a snapshot of a mounted file system which has shared access, perform the following

steps:

1. On the master node of the cluster, use the following command to make a full-sized snapshot,

snapvol, of the volume containing the file system 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.

For example, to take a snapshot of the volume cfs_vol in the shared disk group

exampledg:

# vxsnap -g exampledg make source=cfs_vol/newvol=scfs_vol

If the volume does not have any available plexes, or its layout does not support plex break-off,

use the procedure described in “Creating a Volume for Use as a Full-Sized Instant Snapshot”

on page 23 to prepare an empty volume for the snapshot, and then use the following command

to create the snapshot:

# vxsnap -g volumedg make source=volume/snapvol=snapvol

Note This step sets up the snapshot volumes ready for the backup cycle, and starts tracking

changes to the original volumes. When you are ready to make a backup, proceed to

step 2.