[SOLVED] How to increase logical volume to match physical volume, after increasing size of virtualbox virtual drive

mjl3434 · 02-09-2016, 03:04 PM

I need to know how to fix my LVM stuff, so that I can use the 20 GB of space I added to my VirtualBox VM. I ran out of space in my VirtualBox VM. When I initially created the VM I selected "dynamic allocated storage". I mistakenly assumed the virtual hard drive would grow automatically as it ran out of space. Instead I learned that it does not automatically grow, but can be manually increased in size by use of a command line utility in the host OS provided by VirtualBox / Oracle. I backed everything up before making any changes.

So far I have run this command and successfully increased the size of the VM drive:

Code:

C:\Program Files\Oracle\VirtualBox>VBoxManage modifyhd "C:\Users\...path to vm\MyVm.vdi" --resize 40,960
0...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%.

Next I booted to an Ubuntu boot CD and started GParted. From there I disabled the lvm2 pv, and resized /dev/sda2 and /dev/sda5 to take up all of the additional space I just added. Because I do know what what I am doing, and for fear of trashing the existing data, I did not format anything. After these changes I can successfully boot into Ubuntu, but when check out the size of the drive, it looks as if it has not been increased.

Code:

user@zugzwang:~$ df -h
Filesystem                   Size  Used Avail Use% Mounted on
/dev/mapper/ubuntu--vg-root   19G   16G  1.7G  91% /

I found a few commands online to get information about the Logical Volumes, Physical Volumes, and Volume Groups. This is what they show:

Code:

user@zugzwang:~$ sudo lvs
[sudo] password for user: 
  LV     VG        Attr      LSize    Pool Origin Data%  Move Log Copy%  Convert
  root   ubuntu-vg -wi-ao---   18.74g                                           
  swap_1 ubuntu-vg -wi-ao--- 1020.00m            

user@zugzwang:~$ sudo pvs
[sudo] password for user: 
  PV         VG        Fmt  Attr PSize  PFree 
  /dev/sda5  ubuntu-vg lvm2 a--  39.76g 20.02g

user@zugzwang:~$ sudo vgs
[sudo] password for user: 
  VG        #PV #LV #SN Attr   VSize  VFree 
  ubuntu-vg   1   2   0 wz--n- 39.76g 20.02g

As you can see it looks like the problem is that my Physical Volume and Volume Group both show that there is 20 GB free, while the Logical Volume where the actual filesystem resides only has the original 18.74 GB. My question is how do I fix everything so that my filesystem can take advantage of the additional 20 GB of space I added?

AlucardZero · 02-09-2016, 03:15 PM

Code:

lvextend -l +100%FREE /dev/mapper/ubuntu--vg-root
resize2fs /dev/mapper/ubuntu--vg-root

(assuming / is ext3 or ext4)

mjl3434 · 02-09-2016, 03:21 PM

Thank you AlucardZero the commands worked without even having to do it form a Live CD. Can you please explain what this argument is, and how one would find it? "/dev/mapper/ubuntu--vg-root"

Code:

user@zugzwang:~$ sudo lvextend -l +100FREE /dev/mapper/ubuntu--vg-root
[sudo] password for user: 
  Extending logical volume root to 38.76 GiB
  Logical volume root successfully resized

user@zugzwang:~$ sudo resize2fs /dev/mapper/ubuntu--vg-root
[sudo] password for user: 
resize2fs 1.42.9 (4-Feb-2014)
Filesystem at /dev/mapper/ubuntu--vg-root is mounted on /; on-line resizing required
old_desc_blocks = 2, new_desc_blocks = 3
The filesystem on /dev/mapper/ubuntu--vg-root is now 10161152 blocks long.

user@zugzwang:~$ df -h
Filesystem                   Size  Used Avail Use% Mounted on
/dev/mapper/ubuntu--vg-root   39G   17G   20G  46% /

AlucardZero · 02-09-2016, 08:16 PM

It's the device of your root filesystem.

sundialsvcs · 02-10-2016, 08:29 AM

You can either resize the physical file ... note that you might have to tell the LVM that you have done so ... or you can allocate a new physical storage unit – partition, what have you – and add it to the pool. I prefer to do the latter. The thought of "re-sizing" a file system gives me the creeps.