Some time we don’t use some of the mount point and we want to
remove that file system and use that space on some other server. To reclaim the
disk from the server use the Plan of action explained below:
Unmount file system (FS)
Remove Logical Volume (LV)
Reduce/Remove Volume Group (VG)
Remove Physical Volume (PV) from LVM.
Umount file system (FS)
To make sure nobody is
using file system, use the fuser command.
# fuser –cu /data
|
/data:
28212c(user1)
|
u: Display
the login user name in parentheses following each process ID.
c: Display
the use of a mount point and any file beneath that mount point.
Each file must be a file system mount point.
If u
receives the above result then it means user1 is using this mount point, so
check with user1, when he is going to finish his job one done you can process
with the procedure.
To free up busy mount point you can use fuser command with k
option:
k :- Send the SIGKILL
signal to each process using each file.
#fuser -kuc /data
unmount file system
# umount /data
Cross check with #bdf command.
Remove entry form /etc/fstab file for /data file system
Remove Logical Volume (LV)
To remove LV use lvremove command, when prompted, press y to
remove the volume.
#lvremove /dev/vg03/lvol1
|
The
logical volume "/dev/vg03/lvol1" is not empty;
do
you really want to delete the logical volume (y/n) : y
Logical
volume "/dev/vg03/lvol1" has been successfully removed.
Volume
Group configuration for /dev/vg03 has been saved in /etc/lvmconf/vg03.conf
|
If the
logical volume contains data, LVM prompts you for confirmation. You can use the
-f flag to remove the logical volume without a confirmation request.
#lvremove
-f /dev/vg03/lvol1
Reducing/Removing
volume group
To remove
a PV from a volume group, first verify that none of the physical extents (PE)
on the disk are currently in use. Use the pvdisplay command to determine:
#pvdisplay
-v /dev/vg03/disk42
|
---
Physical volumes ---
PE
Size (Mbytes) 8
Total
PE 255
Free
PE 250
---
Physical extents ---
PE
Status LV LE
00001
current /dev/vg03/lvol2 00001
00002
current
/dev/vg03/lvol2 00002
00003
current /dev/vg03/lvol2 00003
00240
free
00000
00241
free 00000
00242
free 00000
|
From the
output we get that some PE is used by some other LV. So you first need to move
these PE to other disk PE in the volume group.
#pvmove /dev/disk/disk42
/dev/disk/disk41
|
Physical volume "/dev/disk/disk42" has
been successfully moved.
Volume Group configuration for /dev/vg03 has been
saved in /etc/lvmconf/vg03.conf
|
Here you are moving disk 42 PE to
the disk 41 and you can run the pvmove command while file systems are mounted
and active.
Now you can reduce volume group
as no part of disk 42 is in use.
#vgreduce /dev/vg03
/dev/disk/disk42
|
Volume group "vg03" has been
successfully reduced.
Volume Group configuration for /dev/vg03 has been
saved in /etc/lvmconf/vg03.conf
|
Verify if there is only one disk
remaining in the volume group. We cannot remove the volume group if there is
more than one physical disk in the volume group.
# vgdisplay -v vg03 |grep
"PV Name"
|
PV Name
/dev/disk/disk41
|
Remove the volume group vg03.
# vgremove vg03
|
Volume group "vg03" has been successfully
removed.
|
Remove the directory and group
DSFs for the volume group. Press y when prompted.
# rm -ir /dev/vg03
|
directory /dev/vg03: ? (y/n) y
/dev/vg03/group: ? (y/n) y
/dev/vg03: ? (y/n) y
|
Remove Physical Volume (PV) From LVM
Remove the LVM headers from both
of the disks using the pvremove command.
# pvremove /dev/rdisk/disk42
|
The physical volume associated with
"/dev/rdisk/disk42" has been removed.
|
