Can I Re-Use Old Media?

Most of people I talk to who have DVD burners are excited about rewritable (RW) discs; discs that can, theoretically, be written to and re-written many times. The idea is very seductive: you get the convenience of having an inexpensive portable backup that you can re-use. Does the reality live up to the dream? In our experience - no, it does not.

We've had nothing but problems with rewritable optical discs. The first big problem we found with them is that 'quick formats' (to blank out a disc so it can be rewritten) don't work. Old data on the disc often comes back! This means that, to have a reliable backup, we need to spend anywhere from 15 minutes to an hour doing a long format on discs that already have data on them.

The second problem is that, especially with DVD-RW discs (whether +RW or -RW) the data on the disc becomes extremely sensitive to scratches. When playing back a movie, it's not such a big deal if a single frame glitches or there's a pop in the audio. However, for data backups, every bit needs to be correct for the backup to be valid… And it's so very easy to scratch a disc when you're constantly taking it out of its jewel case and inserting it into the computer.

We've also discovered that RW discs just aren't reliable after the first few writes. We've gotten burn errors on RW discs after only using them four times, and these discs were not scratched. For an experiment, we would format them and try again; sometimes they would work, sometimes not. A disc that you think contains a backup but in fact contains a bunch of corrupted data can be even more dangerous and frustrating than if you had never made the backup in the first place.

Tapes can be better… depending on the kind of tapes that you use. Another media type we've had trouble with are Travan tapes, though they come with a lifetime warranty. I remember contacting a manufacturer when a Travan tape I was using wore out and died; the lady on the line asked how many times I had used the tape. When I responded that I had no idea, she informed me that they only give warranties on tapes that had no more than four write and four read cycles (i.e. you use the tape four times to back-up, then four times to restore or verify the backup). Basically, they gave a lifetime warranty on tapes as long as they aren't used much. We've had much better luck with DAT tapes and others, but any tape will eventually wear out. It's just a question of when.

In short, we at Warm and Fuzzy Logic do not recommend using rewritable optical discs, whether they are DVD or CD, for backup. We do recommend using the write-once media and keeping a collection of your old backups; the media is cheap and plentiful. For tapes, we don't recommend using tapes past the number of write cycles covered by the manufacturer warrantee. Hard drives, zip disks and other hard-drive-based media don't have nearly the same number of problems.