Extend an LVM partition
15 min
Need sudo
EasyIn this example, we extend one LVM partition by 300GB which is the size of a newly added hard disk. As usual, before doing any manipulation of storage, it is recommended to make backups, especially for sensitive data.
Before we start, let's check current storage usage and definitions by using the command df -h. This command allows us to verify the existing mount points and identify the LVM partition which we want to extend (in our case is /dev/mapper/centos-root).
$> df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 44G 22G 23G 49% /
devtmpfs 3.9G 0 3.9G 0% /dev
tmpfs 3.9G 0 3.9G 0% /dev/shm
tmpfs 3.9G 65M 3.8G 2% /run
tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup
/dev/sda1 1014M 184M 831M 19% /boot
tmpfs 783M 0 783M 0% /run/user/1000Next, we verify the filesystem used by the LVM partition by using command mount | grep /dev/mapper/centos-root (in our case xfs).
$> mount | grep /dev/mapper/centos-root
/dev/mapper/centos-root on / type xfs (rw,relatime,seclabel,attr2,inode64,noquota)Last but not least, we check the situation before we add the new disk using the command fdisk -l.
$> sudo fdisk -l
Disk /dev/sda: 53.7 GB, 53687091200 bytes, 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000ebe68
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2099199 1048576 83 Linux
/dev/sda2 2099200 104857599 51379200 8e Linux LVM
Disk /dev/mapper/centos-root: 47.2 GB, 47240445952 bytes, 92266496 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/centos-swap: 5368 MB, 5368709120 bytes, 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesYou can now add the new disk and then check with the sudo fdisk -l that it appears in the list.
$> sudo fdisk -l
Disk /dev/sdb: 322.1 GB, 322122547200 bytes, 629145600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/sda: 53.7 GB, 53687091200 bytes, 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000ebe68
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2099199 1048576 83 Linux
/dev/sda2 2099200 104857599 51379200 8e Linux LVM
Disk /dev/mapper/centos-root: 47.2 GB, 47240445952 bytes, 92266496 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/centos-swap: 5368 MB, 5368709120 bytes, 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesOnce identified we need to partition the new drive in our example /dev/sdb with the command sudo fdisk /dev/sdb.
We will pick in order the options:
- n (for new partition)
- p (for primary)
- 1 (for partition number 1)
- [Enter] for default first sector
- [Enter] for default last sector
- t (for partition type)
- L (to list the type options)
- the linux LVM type (here 8e)
- w to write the new partition table
$> sudo fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0x580ff4c7.
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-629145599, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-629145599, default 629145599):
Using default value 629145599
Partition 1 of type Linux and of size 300 GiB is set
Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): L
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 39 Plan 9 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 40 Venix 80286 85 Linux extended c7 Syrinx
5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data
6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility
8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt
9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 54 OnTrackDM6 a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 55 EZ-Drive a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 5c Priam Edisk a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f2 DOS secondary
16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT
1e Hidden W95 FAT1 80 Old Minix
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.Then we need to create a new physical volume with the command pvcreate <<newly created partition>>, or in our case:
$> sudo pvcreate /dev/sdb1
Physical volume "/dev/sdb1" successfully created.Listing of the current volume group.
We will use the VG Name so remember it somewhere.
$> vgdisplay
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 3
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 <49.00 GiB
PE Size 4.00 MiB
Total PE 12543
Alloc PE / Size 12543 / <49.00 GiB
Free PE / Size 0 / 0
VG UUID 1pMApR-ZNgz-JJOv-O8o0-qIAe-He1L-3zqlvz
vgextend <<VG Name>> <<newly created partition>>, or in our case
$> sudo vgextend centos /dev/sdb1
Volume group "centos" successfully extendedScanning for physical volumes. You should now see the new volume with 300GB.
$> sudo pvscan
PV /dev/sda2 VG centos lvm2 [<49.00 GiB / 0 free]
PV /dev/sdb1 VG centos lvm2 [<300.00 GiB / <300.00 GiB free]
Total: 2 [348.99 GiB] / in use: 2 [348.99 GiB] / in no VG: 0 [0 ]We can now list the logical volumes using the lvdisplay command.
We want to extend the logical volume with the VG Name we got earlier for the partition root.
$> lvdisplay
--- Logical volume ---
LV Path /dev/centos/swap
LV Name swap
VG Name centos
LV UUID iOYoLK-u8rm-rCUe-8ykC-dZcS-GmuO-mWAJNm
LV Write Access read/write
LV Creation host, time dboracle12.v56, 2018-11-15 15:29:05 +0100
LV Status available
# open 2
LV Size 5.00 GiB
Current LE 1280
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:1
--- Logical volume ---
LV Path /dev/centos/root
LV Name root
VG Name centos
LV UUID U6FIfy-2VNV-oj6Y-bIPN-MPjl-agbV-3e0Jvr
LV Write Access read/write
LV Creation host, time dboracle12.v56, 2018-11-15 15:29:05 +0100
LV Status available
# open 1
LV Size <44.00 GiB
Current LE 11263
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0Now we extend the Logical volume with lvextend <<LV path>> <<newly created partition>>, or in our case
$> sudo lvextend /dev/centos/root /dev/sdb1
Size of logical volume centos/root changed from <44.00 GiB (11263 extents) to 343.99 GiB (88062 extents).
Logical volume centos/root successfully resized.Last step, we extend the filesystem on our logical volume to use all for free space which we added.
Note that we use xfs_growfs because we have xfs filesystem, if we had ext we would use resize2fs <<LV path>>
$> sudo xfs_growfs /dev/centos/root
meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=2883328 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=11533312, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=5631, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 11533312 to 90175488Now you can check the space available with a df -h command.
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 344G 22G 323G 7% /
devtmpfs 3.9G 0 3.9G 0% /dev
tmpfs 3.9G 0 3.9G 0% /dev/shm
tmpfs 3.9G 8.9M 3.9G 1% /run
tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup
/dev/sda1 1014M 184M 831M 19% /boot
tmpfs 783M 0 783M 0% /run/user/1000Recipe published on 2019-01-09