>We have a requirement of taking regular backups of Server files and individual users files.. I'm in a confusion what to buy for that ??
>
>CD-Rewriter ?
>Tape Drives ?
>Zip Drives ?
>

If your primary interest is backup, I'd strongly recommend going with a tape solution; the cost/MB of storage is lower than any of the other options you're considering, and there's a wide range of software that can schedule backups either from a owkstation or with a server-based backup solution. Tapes are reusable easily. A number of different formats are available; the one I use the most is DAT; DDS-3 (the current high-end DAT storage option) can hold up to ~24GB/tape compressed; I use the older DDS-2 formats, which can hold up to about 8GB/tape. DAT is a relatively expensive solution from a hardware standpoint (new DDS-2 units are in the $700-900 range, and DDS-3 solutions are $1000-1500 typically.) DAT has advantages over lower cost solutions in terms of reliability and portability.

The low-end backup solutions are generally based around the Travan technologies. TR-4 units can hold 7-10GB/tape compressed; they aren't as fast as DAT drives, but the hardware costs significantly less money, in the $200-300 range. Meida costs are higher - I pay >$10/DDS-2 DAT tape, which an equivalent Travan tape costs in the $25-30 range. There's more variation in implenmentations between vendors for the Travan drives; while I can take a DAT tape written on one manufacturer's drive and read it on another manufacturer's drive with a fair degree of certainty, I don't have that assurance with Travan backups between vendors.

Of the options you list, Zip drives are the worst choice - they're slow, and will require manual intervention for backups >100MB. The cost per MB of storage is prohibitive as well. n The only thing recommending Zip is that it's fairly portable.

I would not consider CD-RW as a viable backup medium. Again, the drive limits the amount that you can store unattended to the size of a CD (~600-650MB). CD is slow, and depending on the CD software, may require that you create a master image before backup, requiring an equivalent amount of free storage to what you want written to CD. The CD drives usually require that the only activity on the system at the time the CD is being written is writing the CD; pauses can result in unreadable results.

CD has the virtue of writing archival backups; if you need to make a backup that will be readable 10 years from now, the optical CD media is less subject to damage than tape or removable cartridge magnetic storage. It's also readable on a DVD drive, so that it's more likely to still be a viable transfer material 10 years from now.

The cost of CD-RW material is quite high; I can buy CD-R (write once) media for somewhere in the $1-$1.50/blank CD in bulk, with each CD-RW costing more than 10x as much.

Ed