[linux-lvm] LVM reducing.

[Patrick Caulfield]

On Thu, Feb 19, 2004 at 06:49:04PM +0100, Christian Reiss wrote:
> Greetings,
> 
> I am running the LVM2 version now, as LVM1 corrupted the VG.
> So i converted it to LVM2 (figured it would re-do the 
> master-data-thingy), and it works.
> 
> Now, (presumably Heinz :) how can I safely reduce the size under LVM2? 
> LVM1 had this e2fsadm jiggamagic-thingy-thing - anything LVM2 offers to 
> safely reduce the data?

There is no e2fsadm for LVM2.

What I tend to do is to reduce the filesystem by a little more than I need, then
reduce the LV by the "correct" amount, then resize the the filesystem to fill
the LV. It's a little bit of a faff  but it avoids any nasty accidents or
rounding errors:

eg: To remove 2Gig from an LV

# resize_reiserfs -s -2300M /dev/vg00/fs
# lvreduce -L -2G /dev/vg00/fs
# resize_reiserfs /dev/vg00/fs

That works for ext2/3 etc as well as reiser, just use the relevant resize
command.

patrick