Re: LVM and disk failure

[Daniel Webb <lists@danielwebb.us>]

On Sat, Jan 07, 2006 at 09:02:20PM -0800, Mike Bird wrote:

> If you've got enough spindles, each physical volume is typically a RAID1
> or RAID5.  Then you can add and remove physical volumes from
> your volume group as needed.  A single disk failure is harmless.
> 
> Other than adding and removing physical volumes you don't resize
> the volume group.  The logical volumes are readily resizable, as
> are some of the filesystems (e.g. ext2/3) which they can contain.

Well, yes, but supposing you *do* have a failure?  Then what?  Half the
filesystem is still there on the second disk, is it recoverable, and if not,
why not?

I'm getting the impression that spanning volume groups with a logical volume
is a *very* bad idea unless the physical volumes are RAID.