NAS boxes were designed to do NFS and CIFS, right? Why not just use NFS or CIFS to mount to the backup server, treat the NFS/CIFS mount just like any other disk, and back it up to tape that way? A lot of people will say there's nothing wrong with doing it this way. It's certainly the simplest way to do things. Here are a few pieces of advice if you plan on backing up your filer this way:
Your NAS vendor has heard this question before and has probably tested a number of ways to back up their filer. If there are issues with backing up their filers via NFS or CIFS, they will tell you. They may also tell you that mixed volumes that serve both NFS and CIFS should be backed up via CIFS. (Details on why this is often true are provided in the next section.)
One of the most common mistakes people make when backing up via NFS or CIFS is to mount the drive to a normal backup client and back the drives up from that client. The problem with this is that the data travels across the network twice. If possible, mount the NFS or CIFS drives directly to the backup server—via a dedicated connection if possible. This will cut your network traffic in half.
Backing up your filers via an NFS or CIFS mount is often a better option than backing them up via their native utilities. Backing them up this way allows you to treat them as any other filesystem and to use whatever ...