Production Combat: Complete Guide to Linux LVM Disk Resizing

Introduction

Whether in a private or public cloud, the storage space distributed to virtual machines in production environments is generally not very large. However, as business grows, storage space often becomes insufficient, requiring an increase in capacity. This article will introduce how to resize storage space on a Linux system in a private cloud environment.

Preparation

In the virtualization platform, select the disk to be resized, click on resize, enter the new size, click confirm, and wait for the resizing to complete.
Execute df -Th to check the file system type.
Log in to the Linux system and install the growpart tool:

1
sudo yum install -y cloud-utils-growpart

1
sudo apt install -y cloud-guest-utils

For operations in a private cloud production environment for the first time, it is highly recommended to create a backup snapshot beforehand to prevent system crashes caused by operational errors.

Pre-operation Information Check

Check the root directory. Due to program caching, the disk usage frequently exceeds 80%, triggering frequent monitoring alerts, thus the root directory needs to be resized.

1
[root@localhost ~]# df -Th
2
Filesystem                               Type      Size  Used Avail Use% Mounted on
3
/dev/mapper/centos-root                  xfs        31G   22G  9.7G  69% /
4
devtmpfs                                 devtmpfs  7.8G     0  7.8G   0% /dev
5
tmpfs                                    tmpfs     7.8G     0  7.8G   0% /dev/shm
6
tmpfs                                    tmpfs     7.8G   43M  7.7G   1% /run
7
tmpfs                                    tmpfs     7.8G     0  7.8G   0% /sys/fs/cgroup
8
/dev/vda1                                xfs      1014M  145M  870M  15% /boot
9
tmpfs                                    tmpfs     1.6G     0  1.6G   0% /run/user/0
10
/dev/mapper/storage-data                 xfs       994G  724G  271G  73% /data

Originally, 40GB was allocated for the root directory. We are adding 40GB, making the total space 80GB, so there is 40GB shown as unallocated.

1
[root@localhost ~]# lsblk
2
NAME             MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
3
sr0               11:0    1  428K  0 rom
4
vda              252:0    0   80G  0 disk
5
├─vda1           252:1    0    1G  0 part /boot
6
└─vda2           252:2    0   39G  0 part
7
  ├─centos-root  253:0    0   31G  0 lvm  /
8
  └─centos-swap  253:1    0    8G  0 lvm  [SWAP]
9
vdb              252:16   0 1000G  0 disk
10
└─vdb1           252:17   0  994G  0 part
11
  └─storage-data 253:2    0  994G  0 lvm  /data

View current LVM physical volume information:

1
[root@localhost ~]# pvdisplay
2
  --- Physical volume ---
3
  PV Name               /dev/vda2
4
  VG Name               centos
5
  PV Size               <39.00 GiB / not usable 3.00 MiB
6
  Allocatable           yes (but full)
7
  PE Size               4.00 MiB
8
  Total PE              9983
9
  Free PE               0
10
  Allocated PE          9983
11
  PV UUID               b10ba6bb-f834-4586-b2ed-d4cd48a380e7
12

13
  --- Physical volume ---
14
  PV Name               /dev/vdb1
15
  VG Name               storage
16
  PV Size               <994.00 GiB / not usable 2.98 MiB
17
  Allocatable           yes (but full)
18
  PE Size               4.00 MiB
19
  Total PE              254463
20
  Free PE               0
21
  Allocated PE          254463
22
  PV UUID               b2cc8a3b-f303-4aed-9e64-1d7106f8dc2f

View current LVM volume group information:

1
[root@localhost ~]# vgdisplay
2
  --- Volume group ---
3
  VG Name               centos
4
  System ID
5
  Format                lvm2
6
  Metadata Areas        1
7
  Metadata Sequence No  3
8
  VG Access             read/write
9
  VG Status             resizable
10
  MAX LV                0
11
  Cur LV                2
12
  Open LV               2
13
  Max PV                0
14
  Cur PV                1
15
  Act PV                1
16
  VG Size               <39.00 GiB
17
  PE Size               4.00 MiB
18
  Total PE              9983
19
  Alloc PE / Size       9983 / <39.00 GiB
20
  Free  PE / Size       0 / 0
21
  VG UUID               1f9a2057-a09e-4b44-9653-d9a9cdb7bf97
22

23
  --- Volume group ---
24
  VG Name               storage
25
  System ID
26
  Format                lvm2
27
  Metadata Areas        1
28
  Metadata Sequence No  6
29
  VG Access             read/write
30
  VG Status             resizable
31
  MAX LV                0
32
  Cur LV                1
33
  Open LV               1
34
  Max PV                0
35
  Cur PV                1
36
  Act PV                1
37
  VG Size               <994.00 GiB
38
  PE Size               4.00 MiB
39
  Total PE              254463
40
  Alloc PE / Size       254463 / <994.00 GiB
41
  Free  PE / Size       0 / 0
42
  VG UUID               83fd0dd2-03c7-4eb3-abf7-a8e1c8ab03ef

View LVM logical volume information:

1
[root@localhost ~]# lvdisplay
2
--- Logical volume ---
3
LV Path                /dev/centos/swap
4
LV Name                swap
5
VG Name                centos
6
LV UUID                6add95fe-d525-449d-9b73-9220738be6ff
7
LV Write Access        read/write
8
LV Creation host, time localhost, 2024-12-25 16:23:51 +0800
9
LV Status              available
10
# open                 2
11
LV Size                8.00 GiB
12
Current LE             2048
13
Segments               1
14
Allocation             inherit
15
Read ahead sectors     auto
16
- currently set to     8192
17
Block device           253:1
18

19
--- Logical volume ---
20
LV Path                /dev/centos/root
21
LV Name                root
22
VG Name                centos
23
LV UUID                abf6ca1d-ceb0-4cec-a2a7-f510b9dce3b9
24
LV Write Access        read/write
25
LV Creation host, time localhost, 2024-12-25 16:23:51 +0800
26
LV Status              available
27
# open                 1
28
LV Size                <31.00 GiB
29
Current LE             7935
30
Segments               1
31
Allocation             inherit
32
Read ahead sectors     auto
33
- currently set to     8192
34
Block device           253:0
35

36
--- Logical volume ---
37
LV Path                /dev/storage/data
38
LV Name                data
39
VG Name                storage
40
LV UUID                fe6f9801-c930-4aec-9fd0-39e7b39ccfaf
41
LV Write Access        read/write
42
LV Creation host, time localhost.localdomain, 2025-11-03 14:09:57 +0800
43
LV Status              available
44
# open                 1
45
LV Size                <994.00 GiB
46
Current LE             254463
47
Segments               1
48
Allocation             inherit
49
Read ahead sectors     auto
50
- currently set to     256
51
Block device           253:2

Execution of Resize Operations

Expand specified block device size:

1
[root@localhost ~]# growpart /dev/vda 2
2
CHANGED: partition=2 start=2099200 old: size=81786880 end=83886080 new: size=165672927 end=167772127
3
[root@localhost ~]# lsblk
4
NAME             MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
5
sr0               11:0    1  428K  0 rom
6
vda              252:0    0   80G  0 disk
7
├─vda1           252:1    0    1G  0 part /boot
8
└─vda2           252:2    0   79G  0 part
9
  ├─centos-root  253:0    0   31G  0 lvm  /
10
  └─centos-swap  253:1    0    8G  0 lvm  [SWAP]
11
vdb              252:16   0 1000G  0 disk
12
└─vdb1           252:17   0  994G  0 part
13
  └─storage-data 253:2    0  994G  0 lvm  /data

Resize the LVM physical volume:

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[root@localhost ~]# pvresize /dev/vda2
2
  Physical volume "/dev/vda2" changed
3
  1 physical volume(s) resized or updated / 0 physical volume(s) not resized
4
[root@localhost ~]# pvdisplay
5
  --- Physical volume ---
6
  PV Name               /dev/vda2
7
  VG Name               centos
8
  PV Size               <79.00 GiB / not usable 1.98 MiB
9
  Allocatable           yes
10
  PE Size               4.00 MiB
11
  Total PE              20223
12
  Free PE               10240
13
  Allocated PE          9983
14
  PV UUID               b10ba6bb-f834-4586-b2ed-d4cd48a380e7
15

16
  --- Physical volume ---
17
  PV Name               /dev/vdb1
18
  VG Name               storage
19
  PV Size               <994.00 GiB / not usable 2.98 MiB
20
  Allocatable           yes (but full)
21
  PE Size               4.00 MiB
22
  Total PE              254463
23
  Free PE               0
24
  Allocated PE          254463
25
  PV UUID               b2cc8a3b-f303-4aed-9e64-1d7106f8dc2f

Extend the LVM logical volume:

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[root@localhost ~]# lvextend -l +100%FREE /dev/centos/root
2
  Size of logical volume centos/root changed from <31.00 GiB (7935 extents) to <71.00 GiB (18175 extents).
3
  Logical volume centos/root successfully resized
4
[root@localhost ~]# lvdisplay
5
  --- Logical volume ---
6
  LV Path                /dev/centos/swap
7
  LV Name                swap
8
  VG Name                centos
9
  LV UUID                6add95fe-d525-449d-9b73-9220738be6ff
10
  LV Write Access        read/write
11
  LV Creation host, time localhost, 2024-12-25 16:23:51 +0800
12
  LV Status              available
13
  # open                 2
14
  LV Size                8.00 GiB
15
  Current LE             2048
16
  Segments               1
17
  Allocation             inherit
18
  Read ahead sectors     auto
19
  - currently set to     8192
20
  Block device           253:1
21

22
  --- Logical volume ---
23
  LV Path                /dev/centos/root
24
  LV Name                root
25
  VG Name                centos
26
  LV UUID                abf6ca1d-ceb0-4cec-a2a7-f510b9dce3b9
27
  LV Write Access        read/write
28
  LV Creation host, time localhost, 2024-12-25 16:23:51 +0800
29
  LV Status              available
30
  # open                 1
31
  LV Size                <71.00 GiB
32
  Current LE             18175
33
  Segments               1
34
  Allocation             inherit
35
  Read ahead sectors     auto
36
  - currently set to     8192
37
  Block device           253:0
38

39
  --- Logical volume ---
40
  LV Path                /dev/storage/data
41
  LV Name                data
42
  VG Name                storage
43
  LV UUID                fe6f9801-c930-4aec-9fd0-39e7b39ccfaf
44
  LV Write Access        read/write
45
  LV Creation host, time localhost.localdomain, 2025-11-03 14:09:57 +0800
46
  LV Status              available
47
  # open                 1
48
  LV Size                <994.00 GiB
49
  Current LE             254463
50
  Segments               1
51
  Allocation             inherit
52
  Read ahead sectors     auto
53
  - currently set to     256
54
  Block device           253:2

The above steps complete the resizing of the LVM physical and logical volumes. Next, we need to resize the file system itself. Different file system types require different commands, as shown below:

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[root@localhost ~]# xfs_growfs /dev/mapper/centos-root
2
meta-data=/dev/mapper/centos-root isize=512    agcount=4, agsize=2031360 blks
3
         =                       sectsz=512   attr=2, projid32bit=1
4
         =                       crc=1        finobt=0 spinodes=0
5
data     =                       bsize=4096   blocks=8125440, imaxpct=25
6
         =                       sunit=0      swidth=0 blks
7
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
8
log      =internal               bsize=4096   blocks=3967, version=2
9
         =                       sectsz=512   sunit=0 blks, lazy-count=1
10
realtime =none                   extsz=4096   blocks=0, rtextents=0
11
data blocks changed from 8125440 to 18611200

1
sudo resize2fs /dev/mapper/centos-root

Check the final resizing result:

1
[root@localhost ~]# df -Th
2
Filesystem                               Type      Size  Used Avail Use% Mounted on
3
/dev/mapper/centos-root                  xfs        71G   17G   55G  24% /
4
devtmpfs                                 devtmpfs  7.8G     0  7.8G   0% /dev
5
tmpfs                                    tmpfs     7.8G     0  7.8G   0% /dev/shm
6
tmpfs                                    tmpfs     7.8G   43M  7.7G   1% /run
7
tmpfs                                    tmpfs     7.8G     0  7.8G   0% /sys/fs/cgroup
8
/dev/vda1                                xfs      1014M  145M  870M  15% /boot
9
tmpfs                                    tmpfs     1.6G     0  1.6G   0% /run/user/0
10
/dev/mapper/storage-data                 xfs       994G  724G  271G  73% /data

Production Combat: Complete Guide to Linux LVM Disk Resizing

https://www.koevn.com/p/c02c522b/

Author

Koevn

Published at

March 11, 2026

License

CC BY-NC-SA 4.0