[CentOS] Extending LVM2 logical volumes [ was: Demonizing ... ]

[ context from the previous thread ]

On Saturday 28 May 2005 14:41, Collins Richey wrote:
> On 5/28/05, Lamar Owen <lowen at pari.edu> wrote:
> > Sure.  LVM.

> I'm curious about this. At work we haven't finished our evaluation of
> RHEL3/RHEL4 (CentOS is out of the question, since SLA is king here).
> Most of our servers and desktops are RH9 legacy, and we use LVM on all
> of them. It's my understanding that RHEL4(CentOS4) only offers LVM2,
> and it doesn't appear that you can extend an ext3 filesystem using
> LVM2 tools. If that is indeed true, why woud LVM be "measurably
> better?

While I am no LVM expert, it seems that ext2online does what you want.  My
CentOS4 box here has ext2online included; I have not had a chance to try it
out, so I can't comment on how well it works.

However, what I have read is that the LVM2 metadata format is more robust and
removes many of the limitations of LVM1.  In trying to check on this, I
looked for specific information on how this was the case, but have not been
able to at this point.

The ext2/3 filesystem wasn't designed for resizing online, so it's quite nice
one can do it at all; but it appears the LVM2 approach is to rely on the
e2fsprogs to do the work, so, taking you question literally, no, there is no
LVM2 tool to resize; you would do a two-step, resizing the logical volume
then resizing the filesystem with e2fsprogs. But, having never had
opportunity to do this, I have no direct experience with it.

---

So, has anyone found an equivalent (even multiple commands that I
could put in a script) for the e2fsadm utility to extend a logical
volume? Anyone who has experience with ext2online?

-- 
 Collins
       Head teachers of the world unite: you have nothing to lose but 
       the Start button.