Volume Groups

This page will be a rough guide on creating Volume Groups required for Virtualizor KVM and Xen.

• First we need to check if there is an LVM partition on the server. Run this command:

# fdisk /dev/sda 

• Then type the following to print the partition scheme:

The following command are to be run from inside the fdisk tool:

p

The output will be like so:

Device Boot      Start         End      Blocks   Id  System 
/dev/sda1   *           1       13055   104856576+  83  Linux 
/dev/sda2           13055       13565     4094976   82  Linux swap / Solaris 
/dev/sda3           13565      243201  1844558432   8e  Linux 

Creating New Partition

We need to create a Linux LVM partition on the /dev/sda3.
The following commands are to be run from inside the fdisk tool:

• Delete the third partition: (only if required on your server)

d <enter>  (Delete a partition)
3 <enter> (Select the partition number) 

• Create a new partition :

n <enter>   (Create a new partition)
p <enter>   (It should be a primary partition)
3 <enter>   (This will become the third partition)
<enter>     (Use default calculated value for start cylinder
<enter>     (Use default calculated value for end cylinder)
t <enter>   (Change the partition type)
3 <enter>   (Select the partition number)
8e <enter>  (Partition type will be 8e) 

• Write the changes to the partition table

w <enter> 

• Reboot the server

# reboot

• After reboot, the partition scheme should look like this

/dev/sda1   *           1       13055   104856576+  83  Linux 
/dev/sda2           13055       13565     4094976   82  Linux swap / Solaris 
/dev/sda3           13565      243201  1844558432   8e  Linux LVM 

• Now, the physical volume and the volume groups need to be created.

# pvcreate /dev/sda3

NOTE: If you are using RAID setup on your server, please create the PV from RAID disks (e.g. /dev/md1) and not from the actual disks (e.g /dev/sda1).
Please note that disk names can be different as per your setup, above explanation is just for an example.

• Create the Volume Group (VG)

# vgcreate vg /dev/sda3

NOTE: If you are using RAID setup on your server, please create the VG from RAID disks (e.g. /dev/md1) and not from the actual disks (e.g /dev/sda1).
Please note that disk names can be different as per your setup, above explanation is just for an example.

Existing LVM

• Incase an lvm is already created and the lv is mounted un-necesarrily, then you can un-mount it.

Filesystem        Type      Size  Used Avail Use% Mounted on 
/dev/md3          ext4       58G  2.5G   53G   5% /   
/dev/md2          ext4      3.9G   64M  3.6G   2% /boot
/dev/mapper/vg-vg ext4      3.4T   70M  3.2T   1% /vgs

above is the sample output of df -Th command

• You can un-mount using below command

# umount /vgs

• Then remove the lv mounted on /vgs directory

# lvremove /dev/vg/vg

• And comment its entry in /etc/fstab file
• Then add /dev/vg as lvm based storage on panel.