Ubuntu Expanding Root Partition Not Worked

Question

I attempted to use lvextend to enlarge the main partition to use up the rest of the space on the disk (about 10GB more), but it seems to have not worked, with system monitor and df still reporting the original size (about 9GB).

lvdisplay
--- Logical volume ---
LV Path                /dev/ubuntu-vg/root
LV Name                root
VG Name                ubuntu-vg
LV UUID                d8r0nV-xVlJ-h1gA-QCaa-hXYg-71Aq-orkCu6
LV Write Access        read/write
LV Creation host, time ubuntu, 2014-05-15 20:52:28 +0100
LV Status              available
# open                 1
LV Size                18.76 GiB
Current LE             4802
Segments               2
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           252:0

df
Filesystem                  1K-blocks     Used Available Use% Mounted on
/dev/mapper/ubuntu--vg-root   8907816  3835428   4596844  46% /

Did I miss something?

Answer 1

If you haven't done so yet, you will have to resize the file system. For ext4, I believe the command would be resize2fs /dev/ubuntu-vg/root

A reboot may be necessary afterwards.

**edit: You may need to boot from a live CD because the root partition may need to be unmounted for this to work.