Disk-based backup has been around for a long time now.  I remember when I first deployed a Data Domain DD560 appliance eight years ago. I was impressed by its deduplication technology.  Data domain appliances are disk storage arrays used primarily for backup.  We used it as a disk backup destination for Symantec Netbackup via NFS.  Data Domain sets itself apart because of its deduplication technology.  For instance, in our environment, we are getting a total compression (reduction) of 20x; which means that our 124TB data only uses 6TB of space – a very large space savings indeed.

In addition, disk-based backup makes it very fast and easy to restore data. The need to find the tapes, retrieve them, and mount them have been eliminated.

In fact, the need for tapes can be totally eliminated.  A lot of companies are still using tapes to store them off site for disaster recovery.  If you have a remote office site, a Data Domain appliance can be replicated to your remote site (or disaster recovery site).  What is nice about Data Domain replication is that only the deduped data is sent over the wire.  This means less bandwidth consumption on your WAN (Wide Area Network).

Deduplication technology is getting better. Storage vendors and backup software vendors are offering it in different flavors.  With the cost of disk going down, there is really no need for tapes. Even long term retention and archiving of data can now be stored on a low cost, deduped disk storage array.