> If we add hard drive storage for backups instead of buying LTO-3 tape > drive, how much storage would we want for backing up 2Tb of binary > data...surely not 6 Terrabytes? assuming that three week rotation is full backups only, then 2x3 is indeed 6. However, most people do incremental backups daily and fulls once a week. If this the case, you will need more. Your backups will probably be compressing the files, or rather, archiving them into tarballs, cpioballs, or whatever. However, JPGs and most movie formats will not compress well as they are already compressed very heavily. So a full 2G backup will likely cost you 2G. There are a lot of factors involved and there is a lot more to setting up a good backup regime than figuring out how much disk to throw at a problem. Come the first disaster, they won't be your customer any more. -- Spiro Harvey Knossos Networks Ltd 021-295-1923 www.knossos.net.nz -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 197 bytes Desc: not available URL: <http://lists.centos.org/pipermail/centos/attachments/20080917/210d9fdc/attachment-0005.sig>