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This procedure requires a recent backup of the LVM configuration. This can be generated with the command vgcfgbackup and is stored in the file /etc/lvm/backup/<volume group name>. The /etc/lvm/archive directory also contains recent configurations that are created prior to any changes.

Assuming a physical volume has been lost that was a part of a volume group (for what ever reason), the following procedure can be followed. The procedure will add another physical volume to the volume group to restore the volume group status and access any data that may be able to be recovered.

The procedure for recovery is as follows:

1. Execute:

   vgdisplay --partial --verbose

   The out put will be similar to below:

       Partial mode. Incomplete volume groups will be activated read-only.
       Finding all volume groups
       Finding volume group "volGroup00"
     Couldn't find device with uuid ƏeWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j'.
     Couldn't find device with uuid ƏeWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j'.
     Couldn't find device with uuid ƏeWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j'.
     Couldn't find device with uuid ƏeWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j'.
     --- Volume group ---
     VG Name               volGroup00
     System ID
     Format                lvm2
     Metadata Areas        4
     Metadata Sequence No  33
     VG Access             read
     VG Status             resizable
     MAX LV                0
     Cur LV                1
     Open LV               0
     Max PV                0
     Cur PV                5
     Act PV                5
     VG Size               776.00 MB
     PE Size               4.00 MB
     Total PE              194
     Alloc PE / Size       194 / 776.00 MB
     Free  PE / Size       0 / 0
     VG UUID               PjnqwZ-AYXR-BUyo-9VMN-uSRZ-AFlj-WOaA6z
   
     --- Logical volume ---
     LV Name                /dev/volGroup00/myLVM
     VG Name                volGroup00
     LV UUID                az6REi-mkt5-sDpS-4TyH-GBj2-cisD-olf6SW
     LV Write Access        read/write
     LV Status              available
     # open                 0
     LV Size                776.00 MB
     Current LE             194
     Segments               5
     Allocation             inherit
     Read ahead sectors     0
     Block device           253:0
   
     --- Physical volumes ---
     PV Name               /dev/hda8
     PV UUID               azYDV8-e2DT-oxGi-5S9Q-yVsM-dxoB-DgC4qN
     PV Status             allocatable
     Total PE / Free PE    48 / 0
   
     PV Name               /dev/hda10
     PV UUID               SWICqb-YIbb-g1MW-CY60-AkNQ-gNBu-GCMWOi
     PV Status             allocatable
     Total PE / Free PE    48 / 0
   
     PV Name               /dev/hda11
     PV UUID               pts536-Ycd5-kNHR-VMZY-jZRv-nTx1-XZFrYy
     PV Status             allocatable
     Total PE / Free PE    48 / 0
   
     PV Name               /dev/hda14
     PV UUID               OtIMPe-SZK4-arxr-jGlp-eiHY-2OA6-kyntME
     PV Status             allocatable
     Total PE / Free PE    25 / 0
   
     PV Name               unknown device
     PV UUID               9eWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j
     PV Status             allocatable
     Total PE / Free PE    25 / 0

   The --partial flag is required to get the LVM tools to read partial volume group metadata, otherwise the command would fail because a physical volume is missing. Note the lines in the last entry that are bold. The PV UUID is needed for the next step. This contains the UUID of the physical volume that failed.

2. Now add in a fresh (or new) physical volume whether it be another hard drive or recreate a partition on an existing disk and execute:

    pvcreate --restorefile /etc/lvm/backup/<volume group name> --uuid  <uuid> <device> 

   Remember the UUID is the value taken from the output in step 1. So in this example the full command would be:

    pvcreate --restorefile /etc/lvm/backup/volGroup00 --uuid 9eWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j /dev/hda15  
   Couldn't find device with uuid ƏeWicl-1HSB-Fkcz-wrMf-DzMd-Dgx2-Kyc11j'.
     Physical volume "/dev/hda15" successfully created
   

3. Now the new physical volume has been initiated with the UUID of the old physical volume we can now restore the volume groups metadata with:

    vgcfgrestore --file  /etc/lvm/backup/<volume group name > <volume group name>  

   In keeping with this example, the command would be:

   vgcfgrestore --file /etc/lvm/backup/volGroup00 volGroup00
   Restored volume group volGroup00
   

4. To check that the new physical volume is in tact and the volume group is functioning correctly, execute vgdisplay -v.

Note: This will not recover the data lost on the physical partition that failed, it is simply a way to rebuild the volume group without losing your entire configuration.