On Fri, 2002-03-01 at 07:18, Karl E. Jorgensen wrote: > > I would appreciate some input on this but I think the project is probably > > too big for me. They do want mirror disks in case a hard drive crashes but > > don't think they need to go the whole hog with raid control. Then with > > mirror disks do you really need a tape backup? > > Yes. You don't have enough backups until you're knee-deep in them. Or at > least ankle-deep. > > If you were to suffer a failure on the motherboard, disk controller, > power supply (or any of the other single-point-of-failures), it a *good > thing* to be able to restore everything on a different machine. (I admit: > in this case it might be quicker to move one side of the mirror to > another machine). > > Besides: If one of your users accidentally deletes a file, then the > mirroring won't help you. You'll have to restore the file from the tape > and "educate" the user
Or a fire, or a flood, or theft of your server, or terrorists hit your building, or..... There are plenty of things that could get both drives simultaneously. You need off-site backup; if you care enough about the data to bother with disk mirroring, you should also care enough to take a copy off site, somehow.
