Ok, here is the problem. I have a Xubuntu in Virtual box. I have resized the machine HD and added the missing space using GParted to the patrition as seen in this picture:
After resize the new size should be 25 GB.
However when running console I only get:
$ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/xubuntu--vg-root 18G 14G 2,5G 85% /
^--- Size isn't increased to ~25GB --
none 4,0K 0 4,0K 0% /sys/fs/cgroup
udev 1,5G 4,0K 1,5G 1% /dev
tmpfs 302M 860K 301M 1% /run
none 5,0M 0 5,0M 0% /run/lock
none 1,5G 80K 1,5G 1% /run/shm
none 100M 20K 100M 1% /run/user
/dev/sda1 236M 90M 134M 41% /boot
So the question is - how do I safely expand my current FS to full size? I need to add those missing 6GB to my primary patrition.