phanisvara das said the following on 05/06/2012 05:25 AM:
i'm afraid i'm overlooking something obvious, that's why i'm asking here, where many have much more experience with this type of thing.
I suspect we all overlook things - its the old "Where you stand depends on where you sit"//"Context is everything". But Per has a few pertinent observations. 1. RAID is about availability, not backup. 2. Keeping the librarian's /home on the file server using NFS, a very well established technique that dates back to SUN and the 1980s, does address part of your problem. 3. We've discussed using LVM instead of RAID in the past. Its easier to set up LVM mirroring of partitions *AND* you can use LVM to do disk-to-disk backup. 4. Ultimately backup means transferring to another media; tape, removable disk, or something, and archiving it securely. This has nothing to do with RAID or RSYNC. I know, first hand, that a) NFS mount of users home directory works well. b) LVM is easy to set up if you start the disk with it, but pernickity if you try to 'convert' and existing disk, partition or drive. You need to have experience (i.e. have got it wrong catastrophically in the past and figured out why). So start with a new set of drives. If you do that its easy. c) LVM snapshot is in real-time until you tell it to stop. d) You can backup snapshots onto DVD. I have a policy of using 4G partitions to facilitate that. Its nice to have them as mountable file systems. I'm of the opinion that for what I'm doing, RAID-per-RAID is too complex, involves too many decisions and too many drives. With LVM I can use any number of any drive of any old size according to my budget, add them or remove them. KISS. But YMMV. -- A program designed for inputs from people is usually stressed beyond breaking point by computer-generated inputs. -- Dennis Ritchie -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org