What is Disk Mirroring?

What is Disk Mirroring?

In a simple computer, data is stored on a single hard disk. Disk mirroring stores the same data to two separate disks at once. If one disk fails, all the information is still available on the other disk. (This is also known as Raid Level 1.) Disk mirroring costs more, because two hard disks are used where one disk could be used.

The SC101/SC101T can do disk mirroring (RAID 1), however this reduces read/write performance.
It is possible to disks to be mirrored in two different SC101/SC101Ts.
The SC101/SC101T does not (and will not) do disk striping (RAID 0) to increases performance). This is an entirely different technology.

Disk mirroring is not a subsitute for regular backups, since errors such as critical files being deleted by accident will happen at the same time to both mirrored disks. The SC101/SC101T also includes SmartSynch backup software for this purpose.

Some devices, such as those using USB, can be unplugged while they are still powered on. In a similar way, some disk mirroring allows hot swapping of disks, however the SC101/SC101T does NOT allow this.

The advantages of mirroring depend on how critical your data is, and how often you create backups. If you can't afford to lose data under any circumstance, then mirror the disks, and back them up regularly. If you back up once a week, and can afford to lose a maximum of a week's data, then you don't need to mirror at all. Typically, it will be at least a couple years before a disk in a desktop fails, and you may have audible warning before something happens. (Of course, you have no way of knowing how much abuse your network users cause to their own laptops.) You need to decide whether the cost of duplicating the storage, and the inconvenience of SC101/SC101T slower performance is worth the rather small risk of losing a few week's worth your data -- if you're backing up weekly.