LVM or not? Install Breezy

[David Hart]

On Sun, 2005-10-02 at 16:32 +0900, Craig Hagerman wrote:

> Good info Eric. Thanks. What if you have already installed Ubuntu
> WITHOUT LVM, and later want it. Is is possible to changr oe things after
> an install?

Yes it's possible but depends on how you have your hard disk partitioned
currently.

You need enough spare space to create an initial LVM partition so that
you can copy a current partition into a logical volume created in the
LVM.  As you free up your current partitions you can add them to the LVM
'pool'.

I would strongly recommend that you do this from a boot/live CD to
ensure clean copies.

Also be very sure you have read the LVM docs carefully before trying to
put your '/' partition in LVM; it needs special treatment as the
bootloader can't read LVM volumes.  I myself never bother with '/' in
LVM; if I need to set a machine to multi-boot I simply put a few small
normal '/' partitions at the beginning of the hard disk.

> 
> I installed ubuntu recently and didn't choose the LVM option. But I
> want to add another big harddive soon and would prefer to have the new
> drive and the big partition from the existing drive to be seen as a
> single disc. A bit of investigation and I found out I probably should
> have set it up with LVM originally. Whoops. Is it possible to redo
> things now?

If you're adding a new hard disk things are even simpler as you'll have
plenty of spare space to create your initial LVM partition(s).

Be aware, though, that if you spread your system across two disks you'll
have approximately doubled the chance of your system becoming hosed due
to disk failure.

Also, to answer another poster elsewhere in the thread, it is possible
to migrate logical volumes from one hard disk to another.

-- 
David Hart <ubuntu at tonix.org>