Logical Volume Manager LVM on Ubuntu Server

Logical Volume Manger, or LVM, allows administrators to create logical volumes out of one or multiple physical hard disks. LVM volumes can be created on both software RAID partitions and standard partitions residing on a single disk. Volumes can also be extended, giving greater flexibility to systems as requirements change. 5.2.1.
Overview
A side effect of LVM’s power and flexibility is a greater degree of complication. Before diving into the LVM installation process, it is best to get familiar with some terms. • Physical Volume (PV): physical hard disk, disk partition or software RAID partition formatted as LVM PV. • Volume Group (VG): is made from one or more physical volumes. A VG can be extended by adding more PVs. A VG is like a virtual disk drive, from which one or more logical volumes are carved. • Logical Volume (LV): is like a partition in a non-LVM system. A LV is formatted with the desired file system (EXT3, XFS, JFS, etc), it is then available for mounting and data storage
On Our Example I add new 10 GM Disk Drive on my Virtual machine

We can see this The original one as 30 GB and Also the New drive 10 GM if we run command
Sudo fdisk -l

- First, create the physical volume, in a terminal execute:
sudo pvcreate /dev/sdb

Create Volume group first by command
Vgcreate VG0 /dev/sdb

Format your new Volume using command
Mkfs.ext4 /dev/sdb

Then we can create directory were we want to mounted our new disk using command:
Mkdir desk
Then we will mount our new desk to this directory by using command
Mount /dev/sdb desk

Now we can see our new desk showing under command DF

Then we can also un mounted it by using command
Umount /dev/sdb
And running df again we can not see it
