Ubuntu: How to find unallocated partition/free space?

Question

I've a legacy dedicated server with Ubuntu onboard (console mode only). Based on docs (prices etc.) I see that server must have 250+ GB, but I see significantly less:

$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md1              3.7G  1.6G  2.2G  43% /
none                  2.0G  196K  2.0G   1% /dev
none                  2.0G     0  2.0G   0% /dev/shm
none                  2.0G  3.2M  2.0G   1% /tmp
none                  2.0G   84K  2.0G   1% /var/run
none                  2.0G     0  2.0G   0% /var/lock
none                  2.0G     0  2.0G   0% /lib/init/rw
/dev/mapper/vg00-usr  4.0G  2.2G  1.9G  55% /usr
/dev/mapper/vg00-var  4.0G  1.9G  2.2G  48% /var
/dev/mapper/vg00-home
                      4.0G  1.8G  2.3G  45% /home

I've no idea who/when and how configure that server. Unfortunately, I can't reinstall it from the scratch.

So my question, how can I find free partions/unallocated spaces?

Just in case it's so easy:

$ fdisk -l

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x4ed88842

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1         487     3911796   fd  Linux raid autodetect
/dev/sda2             488         731     1959930   82  Linux swap / Solaris
/dev/sda3             732       60801   482512275   fd  Linux raid autodetect

Disk /dev/sdb: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0b9943b0

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         487     3911796   fd  Linux raid autodetect
/dev/sdb2             488         731     1959930   82  Linux swap / Solaris
/dev/sdb3             732       60801   482512275   fd  Linux raid autodetect

Disk /dev/md1: 4005 MB, 4005560320 bytes
2 heads, 4 sectors/track, 977920 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/md1 doesn't contain a valid partition table

Disk /dev/md3: 494.1 GB, 494092484608 bytes
2 heads, 4 sectors/track, 120628048 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/md3 doesn't contain a valid partition table

Solution

You have two 500GB hard disks. They are configured to have the first partition (4 GB) mirrored as a RAID for / (/dev/md1), two 2 GB partitions (one on each disk) for swap and another RAID mirror taking up the remaining space (/dev/md3).

I assume that /dev/md3 is configured as a physical volume for LVM, containing the volume group vg00, which in turn has three 4GB volumes (for /home, /usr and /var).

You can check the status of the LVM with vgdisplay and either extend existing volumes with lvextend or create new ones in the empty space with lvcreate.

For more infos, see the manual pages for the commands I listed.

Comments

[FoxyBOA]

In my case it was sequence of lvextend + xfs_growfs