Defrag, snapshots, volume usage

Snapshots use CoW (Copy-on-Write). Even if CoW is disabled on a share, CoW is still used at the point in time a snapshot is taken. A defrag breaks the CoW link between the current data and its snapshots.

Our engineers are looking into the snapshot space indicator problem.

1. Yes. The more you change, the more increased usage you would see.

2. Defrags are good. If your volume is getting quite full it would be a good idea to free up some space before running a defrag.

3. Snapshots will still work but they will consume more space and thus make less efficient use of space.

4. Yes, they are just as good practice to run with snapshots as without. A balance moves data and metadata around in order to empty chunks so they can be returned to unallocated space. Again you should keep volume usage to reasonable levels. If volume usage is very high then especially if a balance has not been run for quite some time it's possible the volume will become fully allocated and amongst other problems a balance may fail (though on 6.3.x this is less likely to happen).

Backups are important. No important data should be stored on just the one device.