How to extend root (cs-root) Filesystem using LVM Cent OS/RHEL/Almalinux

This guide will walk you through on how to extend and increase space for the root filesystem on a alma linux. Cent OS, REHL Server/Desktop/VM

Check the current space available

sudo df -h 
Notes -
If you have 0% ~1MB left on the cs-root command auto-complete with tab and some of the later commands wont work, You should clear up atleast 4-10mb by clearing log files, temp files, etc

Mount an additional disk to the VM (Assuming this is a VM) and make sure the disk is visible on the OS level

sudo lvmdiskscan

OR

sudo fdisk -l

Confirm the volume group name

sudo vgs

Lets increase the space

First lets initialize the new disk we mounted

sudo mkfs.xfs /dev/sdb

Create the Physical volume

sudo pvcreate /dev/sdb

extend the volume group

sudo vgextend cs /dev/sdb
  Volume group "cs" successfully extended


Extend the logical volume

sudo lvextend -l +100%FREE /dev/cs/root

Grow the file system size

sudo xfs_growfs /dev/cs/root

Confirm the changes

sudo df -h

Just making easy for us!!

#CentOS

sudo lvmdiskscan
sudo fdisk -l
sudo vgs
sudo mkfs.xfs /dev/sdb
sudo pvcreate /dev/sdb
sudo vgextend cs /dev/sdb
sudo lvextend -l +100%FREE /dev/cs/root
sudo xfs_growfs /dev/cs/root
sudo df -h

#AlmaLinux

sudo lvmdiskscan
sudo fdisk -l
sudo vgs
sudo mkfs.xfs /dev/sdb
sudo pvcreate /dev/sdb
sudo vgextend almalinux /dev/sdb
sudo lvextend -l +100%FREE /dev/almalinux/root
sudo xfs_growfs /dev/almalinux/root
sudo df -h