Legato backup to SAN and MSA Snapshotting

Hi,

as long as your disk storage system is built in a way to assure integrity of data (some sort of RAID) I don't really see any benefits of snapshotting the NetWorker's disk devices.

Snapshotting as technology is best suited for elimination of logical errors, accidental deletions and for general integrity of stored data. Since NetWorker stores data in rather robust way to storage, I must admit that I have never seen NetWorker making logical errors writing to storage, neither have i seen NetWorker accidentally deleting its own stored data. Administrative errors can happen - but they shouldn't justify snapshotting of disk storage. And, like I said, data integrity should be handled by RAID or similar.

In short, I cannot think of the damage that can be done to first copy of data stored where snapshot might be a perfect solution for a problem. I'd expect perhaps general disk problems, or problems with MSA box itself - but its nothing where snapshot might come in handy. If insisting on it it is clear - snapshots need to be taken first thing in the morning after nightly backups - but what good would it do... that's another story.

Anyone else with opinion on this?

Since the disk is only going to contain incremental level backups, snapshotting this seems useless to me; it serves no usefull purpose: my full resides on tape; this will not protect, as previously mentioned, against accidental deletes from any of the networker databases.

Regards,

René