4:29 - Friday, 25 April 2014

How To Move / Copy Logical Volume (lv) To Another Volume Group (vg)?

#Topics: copy lv to to different volume group

Basically, I want to move / copy several logical volumes (lv) into a new volume group (vg). The new volume group reside on a new set of physical volumes. Does anyone know how to do that safely without damaging to the data inside those logical volumes??

Okay, I was able to handle the situation in my own way. Here are the steps I took:

1) Take a snapshot of the targeting logical volume.

lvcreate --snapshot --name --size /dev/volume-group/logical-volume

Note : Size of the snapshot can be as large as or as small as you wish. What matters is having enough space to capture changes during snapshot period.

2) Create an image copy of the snapshot content using dd

dd if=/dev/volume-group/snapshot-name of=/tmp/backup.img

3) Create a new logical volume of enough size in the targeting (new) volume group.

lvcreate --name --size the-new-volume-group-name

4) Write data to the new logical volume from the image backup using dd

dd if=/tmp/backup.img of=/dev/new-volume-group/new-logical-volume

5) delete the snapshot and image backup using lvremove and rm respectively.

That’s all folks… Hope this helps to someone :)