Examples of creating snapshot file systems

In the following examples, the vxdump utility is used to ascertain whether /dev/rdsk/fsvol/vol1 is a snapshot mounted as /backup/home and does the appropriate work to get the snapshot data through the mount point.

These are typical examples of making a backup of a 300,000 block file system named /home using a snapshot file system on a Volume Manager volume with a snapshot mount point of /backup/home.

To create a backup using a snapshop file system

  1. To back up files changed within the last week using cpio:
      # mount -t vxfs -o snapof=/home,snapsize=100000 \
      /dev/vx/dsk/fsvol/vol1 /backup/home
      # cd /backup
      # find home -ctime -7 -depth -print | cpio -oc > /dev/st1
      # umount /backup/home
  2. To do a level 3 backup of /dev/vx/rdsk/fsvol/vol1 and collect those files that have changed in the current directory:
      # vxdump 3f - /dev/vx/rdsk/fsvol/vol1 | vxrestore -xf -
  3. To do a full backup of /home, which exists on disk /dev/vx/rdsk/fsvol/vol1, and use dd to control blocking of output onto tape device using vxdump:
      # mount -t vxfs -o snapof=/home,snapsize=100000 \
      /dev/vx/dsk/fsvol/vol1 /backup/home
      # vxdump f - /dev/vx/rdsk/fsvol/vol1 | dd bs=128k > /dev/st1