VxVM: How to attach&sync / de-attach a volume for backups?

> Let say I have a Volume created within a diskgroup

> on a specific LUN.

> How can I sync it with another volume on another LUN

> so that the new one is synchronized with the first

> one?

Create a mirror and give the storage on the new LUN as the storage specification.

vxassist mirror <volume> [new storage]

> upon successfull attachment and synchronization I

> want to de-attach the second and back it up to tape

> for example...

You might want to do that at the filesystem level instead of the volume level. Also, if you have flashsnap or the enterprise level, there are additional features such as fast resync.

If you have to do this at the volume level, you'd need to dissociate the new plex from the volume, create a new volume using that plex, then start the volume. The data will be there.

--

Darren

Darren_Dunham at 2007-7-7 3:14:01 >

Filesystem snapshots/checkpoints are also available. Check the filesystem admin guide and the mount_vxfs, fsckptadm man pages.

Volume snapshots -

require additional storage space equal to the volume

must copy all blocks of the volume (or need flashsnap for incrementals)

have no I/O impact when exported due to separate storage

usually require the filesystem be unmounted to guarantee consistency

Filesystem checkpoints -

require only storage for changes, not the entire volume

snapshot and live data remain on same device

guarantees filesystem consistency

If you have to do the backups off-host, then checkpoints/VxFS snapshots aren't the solution (or at least not all of the solution).

Darren_Dunham at 2007-7-7 3:14:01 >