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# Tested on RHEL 5.2
# I need to free up and remove /dev/sdc disk from my system. As it makes part of "datavg" # Volume Group, and since it is not 100% free, I'll need to move the data from to another # disk first. # For that, I've added a new disk, /dev/sdd, to transfer all the allocated extents from # /dev/sdc pvs PV VG Fmt Attr PSize PFree /dev/sda2 rootvg lvm2 a- 11.72G 864.00M /dev/sdb datavg lvm2 a- 30.00G 0 /dev/sdc datavg lvm2 a- 5.00G 2.97G <---- In use /dev/sdd datavg lvm2 a- 15.00G 15.00G <---- Free # 'pvdisplay' command used with '-m' option shows the mapping of physical extents to logical # volumes that are spread across my disk. These are the physical extents that I will transfer # to the new disk pvdisplay -m /dev/sdc --- Physical volume --- PV Name /dev/sdc VG Name datavg PV Size 5.00 GB / not usable 3.81 MB Allocatable yes PE Size (KByte) 4096 Total PE 1279 Free PE 761 Allocated PE 518 PV UUID 8JS7oV-6SYK-dQX9-1X24-oxG6-GBEO-Zh9Gce --- Physical Segments --- Physical extent 0 to 286: Logical volume /dev/datavg/lvData Logical extents 4703 to 4989 Physical extent 287 to 517: Logical volume /dev/datavg/lvApp Logical extents 762 to 992 Physical extent 518 to 1278: FREE # If there is sufficient space in destination disk, it will be enough to run 'pvmove' # command indicating both origin and destination disk like this: # ('-i' reports the progress of the move at five second intervals) pvmove -i5 /dev/sdc /dev/sdd /dev/sdc: Moved: 10.4% /dev/sdc: Moved: 21.4% /dev/sdc: Moved: 32.6% /dev/sdc: Moved: 43.6% /dev/sdc: Moved: 44.6% /dev/sdc: Moved: 54.2% /dev/sdc: Moved: 64.1% /dev/sdc: Moved: 73.9% /dev/sdc: Moved: 84.0% /dev/sdc: Moved: 93.8% /dev/sdc: Moved: 100.0% # Once operation done, we can see that /dev/sdc is 100% free and that the number of PFree # on /dev/sdd has been reduced pvs PV VG Fmt Attr PSize PFree /dev/sda2 rootvg lvm2 a- 11.72G 864.00M /dev/sdb datavg lvm2 a- 30.00G 0 /dev/sdc datavg lvm2 a- 5.00G 5.00G <---- Free /dev/sdd datavg lvm2 a- 15.00G 12.97G <---- In use # Now all the Physical Extents of /dev/sdc are free. The allocated ones have been # transferred to /dev/sdd pvdisplay -m /dev/sdc --- Physical volume --- PV Name /dev/sdc VG Name datavg PV Size 5.00 GB / not usable 3.81 MB Allocatable yes PE Size (KByte) 4096 Total PE 1279 Free PE 1279 Allocated PE 0 PV UUID 8JS7oV-6SYK-dQX9-1XMO-oxG6-GBEO-Zh9Gce --- Physical Segments --- Physical extent 0 to 1278: FREE pvdisplay -m /dev/sdd --- Physical volume --- PV Name /dev/sdd VG Name datavg PV Size 15.00 GB / not usable 4.00 MB Allocatable yes PE Size (KByte) 4096 Total PE 3839 Free PE 3321 Allocated PE 518 PV UUID 9Rsa40-n4I2-l3m5-sEH4-VDNX-AqYl-Gj9euZ --- Physical Segments --- Physical extent 0 to 230: Logical volume /dev/datavg/lvApp Logical extents 762 to 992 Physical extent 231 to 517: Logical volume /dev/datavg/lvData Logical extents 4703 to 4989 Physical extent 518 to 3838: FREE # Everything is ready for removing the disk ('vgreduce', 'pvremove', etc,..) # ------------------------------------------------------------------------------------------ # 'pvmove' supports also following options: # No destination disk specified: Move all allocated space off the physical volume to other # free physical volumes in the volume group, if any: pvmove /dev/sdc # Move just the extents of the specified logical volume (See 'pvdisplay -m' here before) to # other free physical volumes in the volume group: pvmove -n lvData /dev/sdc # Run the command in the background, '-b': pvmove -b /dev/sdc /dev/sdd |