[CentOS] LVM: Shrinking a physical partition

Michael Ubell ubell at sleepycat.com
Tue Jan 17 19:10:34 UTC 2006


When I installed CentOS 4 it created a LVM partition
occupying the bulk of my disk.  I would like to trim it
back so I can put another partition for another (thrid)
operating system.

I found some directions that I thought would let me do
this.  I used resize2fs to resize the filesystem and lvreduce
to resize the logical volume.

My problem is that I cannot reduce the size of the partition.
When I do, I get errors when I try to boot:

   Found volume gdevice-mapper: dm-linear: Device lookup failed
roup "VolGroup00device-mapper: dm-linear: Device lookup failed
" using metadataKernel panic - not syncing: Attempted to kill init!
   type lvm2
   device-mapper ioctl cmd 9 failed: Invalid argument
   Couldn't load device 'VolGroup00-LogVol00'.
   device-mapper ioctl cmd 9 failed: Invalid argument
   Couldn't load device 'VolGroup00-LogVol01'.

Here is the current configuration:

lvm> vgs
   VG         #PV #LV #SN Attr  VSize   VFree
   VolGroup00   1   2   0 wz--n 154.03G 78.06G
lvm> lvs
   LV       VG         Attr   LSize   Origin Snap%  Move Log Copy%
   LogVol00 VolGroup00 -wi-ao  75.00G
   LogVol01 VolGroup00 -wi-ao 992.00M
lvm> vgdisplay
   --- Volume group ---
   VG Name               VolGroup00
   System ID
   Format                lvm2
   Metadata Areas        1
   Metadata Sequence No  4
   VG Access             read/write
   VG Status             resizable
   MAX LV                0
   Cur LV                2
   Open LV               2
   Max PV                0
   Cur PV                1
   Act PV                1
   VG Size               154.03 GB
   PE Size               32.00 MB
   Total PE              4929
   Alloc PE / Size       2431 / 75.97 GB
   Free  PE / Size       2498 / 78.06 GB
   VG UUID               P8ykKE-BJgP-tOkw-IgU3-btPA-54Ge-7JlcHn

I would like to shrink the size of the Volume Group.
Here is my partition table:
    Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *         554       10280    78132127+   7  HPFS/NTFS
/dev/sda2               1         553     4441941   1b  Hidden W95 FAT32
/dev/sda3           10281       10293      104422+  83  Linux
/dev/sda4           10294       30401   161517510    5  Extended
/dev/sda5           10294       30401   161517478+  8e  Linux LVM

I thought I could just shrink sda5 to be about 77GB, but that
results in the boot errors.

lvm says that pvresize is not implemented.

Any pointers?

Mike




More information about the CentOS mailing list