Re: about df and lvm

[Bob Proulx]

Philip Rowlands wrote:
> tq01azk wrote:
> >#df -h
> >/dev/mapper/lvtest-lv    4.0G  2.6G  1.3G  68% /mnt/lv
> >#lvextend -L +800M /dev/lvtest/lv
> >Extending logical volume lv to 4.88 GB
> >Logical volume lv successfully resized
> >#df -h
> >/dev/mapper/lvtest-lv    4.0G  2.6G  1.3G  68% /mnt/lv
> 
> Does lvextend affect the logical volume ("partition") size or the 
> mounted filesystem? I think you'll need to run e2extend or other 
> fs-specific tool to expand the filesystem structures, which is what df 
> is reporting.

lvextend only affects the partition.  After extending a partition it
is necessary to run fsck and resizefs.  Assuming ext3 the flow looks
something like this:

  unmount /dev/vg1/lv1
  lvextend -L+1G /dev/vg1/lv1
  e2fsck -f /dev/vg1/lv1
  resize2fs /dev/vg1/lv1
  mount /dev/vg1/lv1

The LVM HOWTOs explain these fairly well.

Bob