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Richard Brown, Think most of the queries have been discussed but a couple of points If you are going raid, 2 discs or more is IMHO practically a must - the advantage of using mirrored discs (Raid 1) is obvious - thus 2 x 250 SATA far preferable to 1 x 500 as there is immediately 1 backup in existence and online for when a disc chews up. Backup is a whole different ballgame though and needs careful thought. There are two completely distinct backup serarios to consider:- 1) the OS system - to enable rapid restoration of the server from bare metal to its operational status. This security can only be taken with 100% certainty when the servers OS system is down having been booted from an external source (eg rescue CD). Only thus can you guarantee absolute file integrity of the dump. This only needs doing after sytem alterations are made and will be very infrequent and can be dumped off to DVD. 2) Data back up - to enable recovery of the servers application filesystem. I strongly favour disc backups made over the network by a dedicated backup machine using tried and tested software - my choice at present being Bacula (available as a download from Sourceforge). Tapes are comparatively expensive and the housekeeping is a pain. You will need to develop a strategy of differential, incremental and full backups depending on the data you are keeping and the cost of data loss should it occur. It is quite feasible to RAID 1 the backup server as well giving yet another copy of the application files. Bear in mind data integrity is still an issue though particularly if using LVM structured filestore, open files with cached writes can cause cross file data inconsistencies in a security copy. It has been posited that the only guaranteed way to achieve data integrity with LVM filestore is to unmout those sections and mount them read only prior to securing them. I have seen snippets of the new O'Reilly book 'Backup and Recovery' which would appear to address a number of these topics and issues - indeed a copy of it is winging it's way towards me as we speak. I'll let you know what I think of it when it gets here (couple of weeks they said!!) David -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html