Nsa Backup - ZyXEL Communications NSA-2400 User Manual

4 Reserved snapshot space can be decreased later, but not increased, so it's better to start
off with a big enough reserved snapshot space.
5 If the disk associated with a volume fails, then all snapshots in that volume are lost.
6 The purging of snapshots occurs after the next snapshot is taken (unlike backup purges
which occur before backup is done).
7 You cannot create snapshots with volumes created using this NSA-2400 release 1 (v1.00
AFA.0 C0) firmware. To overcome this, create a new volume using release 2 firmware,
copy the old volume data over to the new volume and then recreate the old volume. If
you don't have enough space to create a new volume, then use the Genie Backup
Manager to transfer data from your old volume to your computer, recreate the old
volume, and then use the Genie Backup Manager again to back up data from your
computer to the newly created volume.
8 Up to 10 snapshots are allowed in total on the NSA.
9 The NSA uses EVMS (Enterprise Volume Management System) to create snapshots.
6.1.3.2 Snapshots Versus Backups
See Section 6.1.4 on page 85
1 A snapshot only records changes to files within a volume, so it's faster and takes up less
space than backup.
2 You must create a snapshot of a complete volume, not on a single file or folder as you
can do with a backup.
It's a good idea to take both snapshots and backups for the following reasons:
1 Snapshots may become invalid, so it's good to also have backups available in case that
happens.
2 Backups may require several hours depending on the amount of data you have to back up
(it's a good idea to schedule backups at non-peak times), so you should take a snapshot
of your data before the backup is run. If a file becomes corrupt during the backup, you
can still revert to the previous snapshot and back up again.
3 If files to be backed up are open at the time of the backup, then make sure that snapshots
are allowed. If they are allowed and files are open at the time the backup is run, then
backup first takes a snapshot and then copies the files from this snapshot.
If not enough snapshot space is left then the backup will cause your snapshots
to become invalid. The backup will still proceed without the snapshot but if the
open file changes during the backup, then the backup will fail.

6.1.4 NSA Backup

Use the Protect > Backup menus to create data backups to an external USB disk drive or
another NSA over the network. Backup disks must be formatted by the NSA as a disk of type
BACKUP. You cannot back up to other file systems such as NTFS, FAT, or FAT32.
NSA-2400 User's Guide
for more information on backups.
Chapter 6 Protect Screens
85