Backup NAS Devices

A NAS device (Network Attached Storage) is a computer that does nothing but serve as a file storage server for network connected clients. Most NAS devices won’t even have any common input device (no mouse or keyboard) and won’t have any monitor or external devices attached to it. All you’ll see coming out of a NAS device are the network (ethernet) cable and the power cord. Some NAS units have more than one ethernet port, which can be used as a backup port in case of a failure in the main ethernet interface or to split traffic load among them.

Most NAS units are pretty much “plug and play”, which means that they’ll start working as soon as you plug them into your network and the power grid. They work out of the box, but further customization can be achieved by using the setup software, which most of the times, is presented as a web based admin console, although smaller or older NAS units will require the administrator to connect using SSH or Telnet and show a text based configuration menu.

Nowadays you can find NAS units from most major computer brands, including Dell, IBM and HP, and there’s also a wide range of open and closed source projects so that you can turn any PC into a NAS unit, the later are also known as “white box NAS units”.

NAS units can be used as regular file storage or as a storage media for backup software, since most of them will allow you to mount them as virtual filesystems. As NAS units are connected to the local network, the transfer speed can be up to 1 Gbps (1000Mbps) as opposed to Internet based backup storage which will be slower due to Internet bandwidth limits.

Most, if not all, NAS units will allow a multi-user environment, which means that you can use them to store backups from several computers or users and still grant each user access to his or her own backups only. Security isn’t as hard as it would be with online backup systems because a NAS unit is supposed to be behind a firewall and not accessible from the Internet.

Modern NAS units can hold up several Terabytes of data, as more disks can be added to them. Also when a NAS unit reaches it’s capacity limit, be it storage space or CPU limits, it’s possible to add more NAS units and have them act as a cluster or to split the data load on each NAS by network, department or group of users.