Re: [linux-lvm] Possible to raise Max LV?

[Andreas Dilger <adilger@turbolinux.com>]

"zoo1" writes:
> i was also considering creating two VGs, one for "user" data
> and one for "system" stuff. now, i'm trying to figure out what i thought
> the point of this was, maybe something about possible future migrations
> to multispindle systems.

One reason to do this (on AIX) at least was that for production systems
it was useful to be able to move a VG to another server if the original
server died a horrible death.  Also, if you have server failover (HA),
you need to have all of the data in a single VG in order to import it
on the backup server (of course a replicated distributed filesystem is
better).

Finally, on AIX, you have a backup tool called "mksysb" which would give
you a backup tape so that you can install a new/replacement system from
the tape, and it configures all of your LVs for you etc.  The mksysb
backup only backs up the "rootvg", which normally holds /, /usr, /tmp,
/var, /home, /boot, and swap (swap and /tmp are not backed up, but are
re-created at install time).  If you put too much stuff in your rootvg
then it was in danger of not fitting on a single tape, and you also may
restore a lot of junk you don't want on another system.

I've been thinking about doing something like mksysb for Linux, but I
need a bit more support in ext2 (to hold the last mounted directory
for rebuilding /etc/fstab).  Other than that, it would be supremely
convenient for bare-metal restores of a system (only need a boot floppy).

Cheers, Andreas
-- 
Andreas Dilger  \ "If a man ate a pound of pasta and a pound of antipasto,
                 \  would they cancel out, leaving him still hungry?"
http://www-mddsp.enel.ucalgary.ca/People/adilger/               -- Dogbert