Re: [linux-lvm] extending a logical volume

[Pierrick PONS <ppons@cvf.fr>]

> On Jan 21, 2002  19:09 +0100, Pierrick PONS wrote:
> > I've read the extending logical volume section and I can't believe this.
> > According to the doc, it would be impossible to extend a logical volume 
> > without unmounting it first.
> 
> LV resize != fs resize.
> 

Yes you're right. It's possible to extend LV online but it's not the same for 
file systems.


> > I'm using a ext3 (with a 2.4.17 kernel) filesystem and I'd like to extend my 
> > logical volume without unmounting it first. This would be used on a
> > production server, so I can't unmount any logical volume.
> 
> Currently, you cannot online resize ext3, but that is only because the code
> which I wrote to do this for 2.2 was never released, and it has not been
> ported to 2.4/2.5 yet.
> 

It would be a really goud feature .... :-)


> > I've seen that a ext2online patch does exist, maybe this fonctionnality is 
> > still implemented in a newer kernel ?
> 
> No, still only available as a patch.  The ext2 online resizing patch is
> very solid.  The ext3 code is, by necessity, a total rewrite of the code
> to work with ext3 journaling, but the fundamental concepts are the same.
> 
> > Could you give me, if it exists, a method to extend the size without unmount 
> > the logical volume ?
> 
> Use ext2 + ext2online patch (not great, because you probably crash more
> often than you need to resize), use ext3 but no online resizing (offline
> resizing works just fine with ext2resize), or work on porting the ext3
> resizing code to 2.4.
> 

hmmm, I'm not good enough to code this    :-(

So you'd rather use ext3 with offline resizing. 
That is a real problem because LVM would be used on a 24/24 available data 
server with nfs accesses . Datas should be get as often as the other servers 
need to.
Maybe I should have a look at reiserfs + resize-reiserfs instead of using ext3 
. What a pitty, ext3 is easy to install and is jouralised.


> Cheers, Andreas
> --
> Andreas Dilger
> http://sourceforge.net/projects/ext2resize/
> http://www-mddsp.enel.ucalgary.ca/People/adilger/
> 
> 
> 
Thank you Andreas .


Pierrick