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Red Hat Enterprise Linux 6 – How to: migrate data to a new Physical Volume and remove the old PV

  • Add new devices to the system. Use rescan-scsi-bus.sh to scan for new devices or restart the system to get the new devices
  • Create LVM Physical Volumes with the new devices
    • # pvcreate /dev/sdxx
  • Add the devices to the respective VGs
    • # vgextend vgname /dev/sdxx
  • Migrate the data from the existing PV to the new PV
    • # pvmove /dev/sdxx
      • o Where /dev/sdxx is the existing PV that needs to be removed from the VG
  • List the PVs to make sure the PV that needs to be removed has no data on it
    •  # pvs –o+pv_used
      • PV VG Fmt Attr PSize PFree Used
        /dev/sda2 rootvg lvm2 a- 39.51g 8.63g 30.88g
        /dev/sda log2vg   lvm2 a- 30.00g 8.00g 0
        /dev/sde log2vg   lvm2 a- 30.00g 8.00g 22.00g
        /dev/sdf datavg   lvm2 a- 100.00g 5.00g 95.00g
        /dev/sdg log1vg   lvm2 a- 30.00g 8.00g 22.00g
      • In the above example, the data was moved from /dev/sda to /dev/sde (they reside in the same VG)
  • Remove the PV from the VG
    •  # vgreduce vgname /dev/sdxx
  • Remove LVM PV information from the device
    • # pvremove /dev/sdxx
  • Delete the device from system
    •  # echo 1 > /sys/block/sdx/device/delete
    • Or use rescan-scsi-bus.sh to remove the device
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