This action is relevant when you are using the MBR partition table, because this type of partitions has a limitation: 3 main partitions (primary)

We look at the structure

$ lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0    6G  0 disk
├─sda1            8:1    0    1M  0 part
├─sda2            8:2    0  200M  0 part /boot
sda3            8:3    0  5.8G  0 part
  ├─centos-root 253:0    0  5.3G  0 lvm  /
  └─centos-swap 253:1    0  512M  0 lvm  [SWAP]

In this example, the disk sda is equal to 6 Gb

Turn off the machine, expand the disk through virtualization, turn on the machine

Installing the utility growpart (Centos, Rocky Linux)

$ sudo yum -y install cloud-utils-growpart

Installing the utility growpart (Debian)

$ sudo apt -y install cloud-guest-utils

Expanding partition 3 on disk / dev / sda

$ sudo growpart /dev/sda 3

Let’s see what happened

$ lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0  7.8G  0 disk
├─sda1            8:1    0    1M  0 part
├─sda2            8:2    0  200M  0 part /boot
sda3            8:3    0  7.6G  0 part
  ├─centos-root 253:0    0  5.3G  0 lvm  /
  └─centos-swap 253:1    0  512M  0 lvm  [SWAP]

Expanding the physical volume

$ sudo pvresize /dev/sda3
  Physical volume "/dev/sda3" changed
  1 physical volume(s) resized or updated / 0 physical volume(s) not resized

Checking the size of the physical volume

$ sudo pvs
  PV         VG     Fmt  Attr PSize PFree
  /dev/sda3  centos lvm2 a--  7.61g 1.81g

Checking the size of the volume group

$ sudo vgs
  VG     #PV #LV #SN Attr   VSize VFree
  centos   1   2   0 wz--n- 7.61g 1.81g

We check the size of the root size, at the same time we look at the path and type of the file system (in this example, xfs)

$ df -hT | grep mapper
Filesystem               Type      Size  Used Avail Use% Mounted on
/dev/mapper/centos-root  xfs       7.2G  1.7G  5.5G  23% /

Expanding a logical volume

$ sudo lvextend -r -l +100%FREE /dev/mapper/centos-root

Extending the XFS file system

$ sudo xfs_growfs /

Or, we expand the EXT4 file system

$ sudo resize2fs /dev/mapper/centos-root