Resize VM HDD

Let’s assume you want to increase the size of the filesystem /tmp from 3 GB to 5 GB. This can be done online without rebooting the machine. First you should verify if there is enough space left on your volume group:

1[root@examplehost ~]# pvs
2  PV         VG   Fmt  Attr PSize    PFree
3  /dev/sdb   vg00 lvm2 a--  <95.00g <47.00g

In this example you can see that there are 47 GB left.

If there is enough space left you need to re-size the according logical volume first:

1[root@examplehost ~]# df -h /tmp
2Filesystem                      Size  Used Avail Use% Mounted on
3/dev/mapper/vg00-tmplv          3.0G   33M  3.0G   2% /tmp

The filesystem /tmp is located on the logical volume vg00-tmplv. Now that you now where the filesystem is located you can increase it as follows:

1[root@examplehost ~]# lvresize -rL +2G /dev/mapper/vg00-tmplv
2  Size of logical volume vg00/tmplv changed from 3.00 GiB (768 extents) to 5.00 GiB (1280 extents).
3  Logical volume vg00/tmplv successfully resized.

If you now verify the new size of the filesystem it should be 5 GB of size:

1[root@examplehost ~]# df -h /tmp/
2Filesystem              Size  Used Avail Use% Mounted on
3/dev/mapper/vg00-tmplv  5.0G   33M  5.0G   1% /tmp