welcome:linux_usually:lvm
Creating a LVM
Source: doc Ubuntu-fr - LVM
In this example we will create a LVM placed on 2 partitions: sda10 and sdb1
All the command are done with root permissions ⇒ su
or sudo
- if not present, create (with fdisk od gparted or…) the both partitions.
Be careful:all the data stored on these partition will be lost! - create the both physical volumes:
pvcreate /dev/sda10 pvcreate /dev/sdb1
pvdisplay
orpvscan
to get info. - create the volume group “vgBackupPC”:
vgcreate vgBackupPC /dev/sda10 /dev/sdb1
vgdisplay
to get info. - create the logical volume “lvBackupPC” on the entire space of the volume group:
lvcreate -n lvBackupPC -l 100%FREE vgBackupPC
lvdisplay
to get info.
-n
is to give the name and-l
to deal with the storage space ⇒ see the man for more details. - create an ext4 file system on the logical volum:
mkfs -t ext4 /dev/vgBackupPC/lvBackupPC
- mounting the LVM
- with the name of the LVM
mount -t ext4 /dev/vgBackupPC/lvBackupPC /mount/point
- with the UUID
This is a little bit tricky: the UUID to be used is NOT the UUID of the LV given bylvdisplay
!
For the mounting, we have to use the UUID of the file system:- getting the UUID of the file system:
$ blkid /dev/sda1: UUID=.... /dev/sda2: UUID=.... /dev/sda3: UUID=.... .... /dev/mapper/vgBackupPC-lvBackupPC: UUID="521489ca-ba67-49e9-a3c6-fa62b0eeeb2f" TYPE="ext4"
- mounting:
mount -t ext4 UUID=521489ca-ba67-49e9-a3c6-fa62b0eeeb2f /mount/point
Removing a disk from a LVM
In this example we want to remove the disk (= the physical volume more exactly) dev/sdb1
from the LVM.
- Have a look at the general situation:
# pvs -o+pv_used PV VG Fmt Attr PSize PFree Used /dev/sda8 vgBackupPC lvm2 a-- 363,51g 0 363,51g /dev/sdb1 vgBackupPC lvm2 a-- 931,51g 0 931,51g
- Check if there is enough place on the other physical volume to get sdb1 out of the LVM:
# df -h /mnt/dd_affa/ Sys. de fichiers Taille Utilisé Dispo Uti% Monté sur /dev/mapper/vgBackupPC-lvBackupPC 1,3T 287M 1,2T 1% /mnt/dd_affa
So only 287MB are used, so the volume /dev/sda8 can contain all the data.
- Unmount the LVM
# umount /mnt/dd_affa
- Reduce the size of the file system, a bit more that would be necessary the remove sdb1 ⇒ 1,1TB
# lvresize --resizefs --size -1,1T /dev/mapper/vgBackupPC-lvBackupPC
- Empty sdb1 of the LVM (=transfer the data to the remaining volumes)
# pvmove /dev/sdb1
- Remove sdb1 from the LVM:
# vgreduce vgBackupPC /dev/sdb1
- Delete the physical volume:
# pvremove /dev/sdb1
- Grow the remaining file system of the LVM to the maximal size again:
# resize2fs /dev/mapper/vgBackupPC-lvBackupPC
welcome/linux_usually/lvm.txt · Dernière modification : de 127.0.0.1