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How to do a full restore if you wiped all your LVM’s

I’m sure some of you have had the wonderful opportunity to experience loosing all your LVM info in error. Well all is not lost and there is hope. I will show ya how to restore it.

The beauty of LVM is that is naturally creates a backup of the Logical Volumes in the following location.

  • /etc/lvm/archive/

Now If you had just wiped out your LVM and it was simply using one physical disk for all your LVM’s you could simply do a full restore doing the following.

      • vgcfgrestore -f /etc/lvm/archive/(volumegroup to restore) (destination volumegroup)
        o    (ie.)vgcfgrestore -f /etc/lvm/archive/vg_dev1_006.000001.vg vg_dev

If you had multiple disks attached to your volume group then you need to do a couple more things to be able to do a restore.

  • Cat the file /etc/lvm/archive/whatevervolumgroup.vg file you should see something like below
  • physical_volumes {

                        pv0 {

                                    id = “ecFWSM-OH8b-uuBB-NVcN-h97f-su1y-nX7jA9”
                                    device = “/dev/sdj”         # Hint only
                                    status = [“ALLOCATABLE”]
                                    flags = []
                                    dev_size = 524288000    # 250 Gigabytes
                                    pe_start = 2048
                                    pe_count = 63999          # 249.996 Gigabytes
                        }

 

You will need to recreate all the physical volume UUID inside that .vg file for volume group to be able to restore.

    • pvcreate –restore /etc/lvm/archive/vgfilename.vg –uuid <UUID> <DEVICE>

      (IE) pvcreate –restorefile /etc/lvm/archive/vg_data_00122-1284284804.vg –uuid ecFWSM-OH8b-uuBB-NVcN-h97f-su1y-nX7jA9 /dev/sdj
  • Repeat this step for all the physical volumes in the archive vg file until they have all been created.

Once you have completed the above step you should now be able to restore your voluegroups that were wiped

    • vgcfgrestore -f /etc/lvm/archive/(volumegroup to restore) (destination volumegroup)

      o (ie.)vgcfgrestore -f /etc/lvm/archive/vg_dev1_006.000001.vg vg_dev
  • Running the command vgdisplay and pvdisplay should show you that everything is back the way it should be

If you have questions email nick@nicktailor.com

Cheers