Suppose you have two volume groups like vg01 and vg02 and both sizes 5 GB. And vgo1 have no logical volumes but vg02 have two logical volumes.
[root@rhelnode1 /]# vgs
VG #PV #LV #SN Attr VSize VFree
rhel 1 2 0 wz--n- 15.63g 4.00m
vg01 1 0 0 wz--n- 5.00g 4.99g
vg02 2 2 0 wz--n- 5.00g 0.49g
So, you can split both vgs to utilize the space of vgo1.
[root@rhelnode1 /]# vgsplit vg01 vg02 /dev/sdb
Existing volume group "vg02" successfully split from "vg01"
Here you have to specify device path of vg01 (/dev/sdb).
Now you can check vgo1 space splits into vg02.
[root@rhelnode1 /]# vgs
VG #PV #LV #SN Attr VSize VFree
rhel 1 2 0 wz--n- 15.63g 4.00m
vg02 2 2 0 wz--n- 9.99g 5.49g
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Extending filesystem in Linux 7
We have a volumegroup vg01 which have free space then and while creating logical volume we had taken less space.So now we can extend logical volume accordingly.
[root@rhelnode1 /]# vgs
VG #PV #LV #SN Attr VSize VFree
rhel 1 4 0 wz--n- 22.01g 4.00m
vg01 1 1 0 wz--n- 2.00g 1020.00m
[root@rhelnode1 /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg01-backup 1014M 33M 982M 4% /backup
Here we can see vg01 have 1GB free space. So we can extend logical volume named backup by using below command-
[root@rhelnode1 /]# lvextend -L 1.5G /dev/vg01/backup
Size of logical volume vg01/backup changed from 1.00 GiB (256 extents) to 1.50 GiB (384 extents).
Logical volume vg01/backup successfully resized.
Now run below command to extand size of logical volume-
[root@rhelnode1 /]# xfs_growfs /dev/vg01/backup
meta-data=/dev/mapper/vg01-backup isize=512 agcount=4, agsize=65536 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=262144, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 262144 to 393216
After that, we can check our logical volume have updated space.
[root@rhelnode1 /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg01-backup 1.5G 33M 1.5G 3% /backup
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Suppose you have 2 physical volumes in a volume group. But 1 physical volume is sufficient then you can remove another physical volume-
[root@rhelnode1 /]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda3 rhel lvm2 a-- 15.63g 4.00m
/dev/sdb vg02 lvm2 a-- 5.00g 5.00g
/dev/sdc vg02 lvm2 a-- 5.00g 508.00m
[root@rhelnode1 /]# vgdisplay vg02
--- Volume group ---
VG Name vg02
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 5
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 2
Act PV 2
VG Size 9.99 GiB
PE Size 4.00 MiB
Total PE 2558
Alloc PE / Size 1152 / 4.50 GiB
Free PE / Size 1406 / 5.49 GiB
VG UUID vovDvR-WQUV-M0sE-OAZG-emAd-Vw77-Nzdkdv
Here you can see /dev/sdb pv is totally free.then you can reduce your vg by using below command -
[root@rhelnode1 /]# vgreduce vg02 /dev/sdb
Removed "/dev/sdb" from volume group "vg02"
[root@rhelnode1 /]#
Rename of Logical volumes and volume groups -
First of all, you have to change request mode of volume group by using below command :-
[root@rhelnode1 /]# lvchange -a n vg02
[root@rhelnode1 /]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
home rhel -wi-ao---- 7.81g
var rhel -wi-ao---- 7.81g
backup vg02 -wi------- 2.50g
sync vg02 -wi------- 2.00g
[root@rhelnode1 /]# lvrename /dev/mapper/vg02/sync /dev/mapper/vg02-shared
Renamed "sync" to "vg02-shared" in volume group "vg02"
Hint - current lvname with path = /dev/mapper/vg02/sync
New lvname with path = /dev/mapper/vg02-shared
[root@rhelnode1 /]# vgrename /dev/mapper/vg02 /dev/mapper/vg00
Volume group "vg02" successfully renamed to "vg00"
Hint- Current vgname with path = /dev/mapper/vg02
New vgname with path = /dev/mapper/vg00
[root@rhelnode1 /]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
home rhel -wi-ao---- 7.81g
var rhel -wi-ao---- 7.81g
backup vg00 -wi------- 2.50g
vg02-shared vg00 -wi------- 2.00g
[root@rhelnode1 /]#
Now you can change request mode by using below command : -
[root@rhelnode1 /]# vgchange -a y vg00
Volume group "vg00" successfully changed.
Now you can mount your mount point and change also /etc/fstab entries.
How to check your volume group is clustered or non-clustered?
[root@rhelnode1 /]# vgdisplay vg00 --config 'global {locking_type=0}'
WARNING: Locking disabled. Be careful! This could corrupt your metadata.
--- Volume group ---
Clustered yes
If you want convert clustered volume into non clustered volume then use below command -
[root@rhelnode1 /]# vgchange -cn vg00 --config 'global {locking_type=0}'
WARNING: Locking disabled. Be careful! This could corrupt your metadata.
Volume group "vg00" is changed to not clustered.
[root@rhelnode1 /]#
Now successfully changed.
