What is the average daily delta that would need to be transferred? And the net connection? I wonder if an online backup might work for you (eg www.connected.com )

We just dumped our T1 in favor of a 1.5/384 ADSL line since we are no longer hosting anything on-site. I'm not postive that 384Kb is too slow for 2GB/day, but it seems like it to me.

Actually, it would only be slow if you were sitting there watching it. We run our backup at 1AM currently. Maybe we would have to run it earlier to make sure it was done by the morning? In the end, this seems like it would be more expensive as long as the DLT tapes last as long as Tony says. I will look into this and other services more though. Thanks for the idea!

Genixia's got a point.

The online backup site doesn't necessarily need to copy all 2 gigs every night. If the changed data is in a bunch of small files (instead of one huge database file), then you actually only need to back up what's changed, and 384k might be PLENTY for that.

I personally do my backups as a full file-by-file backup every night because I can. It means that in order to get the latest file backup, I need only one good tape out of all the grandfathered copies rather than having to worry about "delta" tapes. And it allows me to go back to any one date within the last few weeks (or a more fuzzy date from within the last year) and pull any version of any file without having to fish through file-change records.

But if you're using an online backup/mirror, then that trickle strategy makes more sense.

I do my backups for my home systems via an online backup over 1024/256 DSL. I currently have 30GB that is protected this way, which works fine because the daily changes to files are rarely more than a couple of hundred MB.

I don't use an online backup service, I have a cheap, quiet Linux box installed on a friend's DSL line and I use a rsync to do the backups at 4am every morning.

I sleep much easier at night now I'm not relying on crappy tape drives (didn't have even DAT) to backup my life's data...

P.S. I'm wishing I had put more than a 120GB disk in the remote Linux box though, as my Canon 10D camera seems to be eating about 1GB of the space a month !