[CentOS] Some basic LVM questions

[Curt Mills]

On Sun, 8 Nov 2009, Monte Milanuk wrote:

> I know everyone says RAID is not substitute for a proper backup
> solution... but this machine *is* the backup for the rest of the
> network.  At what point should one draw the line for backing up?  What
> is there out there that is still reasonably economical for backing up
> say, a RAID 1 setup of two 1TB drives, or a RAID 5 setup of three drives
> that size?  Tape?  Looks to be just about out-stripped in size by cheap
> hard drives, at least in anything even remotely in my price range.  NAS
> - which is probably going to have its own version of RAID?

Perhaps skip using the 13GB drive since it will probably fail
relatively soon.  Snag another larger drive and do mirroring between
the two.

Investigate "Amanda", "Backuppc", or "Duplicity" for doing your
backups from the other boxes.  This way if one drive fails you have
the other still working until you replace it and resync.  The last
two options I listed do de-duping of the disk blocks so you're not
duplicating the same block across backups for multiple machines.  If
you have lots of the same files on the various machines you're
backing up this will save you loads of space (for instance, the same
OS on lots of machines).

If it were me, I'd skip the whole LVM scheme for the house LAN.  Use
real backups schemes and change their configs so that your backups
fit within your available space.  Later on if you run out you can
move things around a bit and go with either LVM or with larger
mirrored drives.  Drives are cheap.

-- 
Curt Mills, WE7U                             hacker at fluke dot com
Senior Methods Engineer/SysAdmin
   "Lotto:  A tax on people who are bad at math."     -- unknown
"Windows:  Microsoft's tax on computer illiterates." -- WE7U
"The world DOES revolve around me:  I picked the coordinate system!"

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