After buying a 120GB external hard drive, I decided to put most of the contents of my old 40GB hard drive on it, so I could wipe a couple of the partitions clean and start afresh. I had 50 per cent of the files backed up onto CD-R or DVD-RAM ? my current backup choices. As I?d put copies of the unbacked-up files onto the brand-new drive, I wiped those partitions and rebooted. Then my nightmare started. The new drive wouldn?t mount.
Immediately I ran Norton Utilities to see if I could rescue the drive. Noooo! It reported an error it couldn?t fix. I spent the rest of the day fiddling around with Norton and re-booting, until, eventually ? and without doing anything that could account for it ? the drive re-appeared on my desktop with all the data intact.
This got me thinking: what would I do if the drive was full of 120GB of data, and it crashed unretrievably. It would take forever to back it up to CD-R or even to any DVD format. I was thinking that maybe I should buy a Sony AIT2 drive. AIT2 holds 50GB, but AIT3 is coming soon with 100GB. AIT uses a ?helical scan?, so it can record high densities on small cartridges. The disadvantage is that the drives need to use precision mechanics and tape guides ? leaving it sensitive to wear over time. These drives are very fast for tape ? offering speeds of around 43GB per hour uncompressed.
Then I heard about the Tandberg Super DLT 320. DLT uses linear technology starting at the beginning of the tape and moving to the end. All the tracks are in parallel to the tape edge. The benefit of this is that the mechanics around the tape are simple and reliable. There are very few moving parts to wear out. SDLT was developed co-operatively by Tandberg and Quantum, and uses a modified DLT recording scheme to offer capacities of 160GB uncompressed and 320GB compressed. The speed is 16MB per second (MBps) uncompressed ? or 32MBps compressed, which translates to an impressive 58GB per hour uncompressed. This drive is currently the fastest in this market segment.
The drive is expensive, as are the tapes. Nevertheless, the cost per megabyte of storage tape is relatively low, and the speed they work at means it will take around two hours to back up a 120GB drive onto the 160GB tape ? with room to spare for 40GB of data.