memo: remove a disk from LVM with shrinking ext3 partition

gistfile1.txt

1. check free space by running "df -h"
=> under 50%, ok

2. unmount the volume

3. dumpe2fs -h /dev/VolGroup00/data
Block count:              10483712
Reserved block count:     524069
Free blocks:              6391697
Free inodes:              2621196
First block:              0
Block size:               4096

4. e2fsck -fC0 /dev/VolGroup00/data
=> /dev/VolGroup00/data: 244/2621440 files (17.6% non-contiguous), 4092015/10483712 blocks

5. resize2fs -p /dev/VolGroup00/data 5000000

6. mount, check size, then unmount

7. lvdisplay
  LV Size                39.99 GiB
  Current LE             10238

8. lvreduce -l 5119 /dev/VolGroup00/data

9. vgdisplay
  Alloc PE / Size       5119 / 20.00 GiB
  Free  PE / Size       5119 / 20.00 GiB

10. e2fsck -fC0 /dev/VolGroup00/data

11. resize2fs -p /dev/VolGroup00/data

12. vgreduce VolGroup00 /dev/xvdg1

13. pvscan 
  PV /dev/xvdf1   VG VolGroup00      lvm2 [20.00 GiB / 0    free]
  PV /dev/xvdg1                      lvm2 [20.00 GiB]

Now we can detach the volume xvdg! (unless any other partitions are used)