Adding and extending disks/volumes in LVM

In order to use LVM, the partition must be type 8e instead of 83 when created by fdisk.

Expand the disk size in your Hypervisor and reboot the linux server.

Create a new partition at the end of the disk:

# fdisk /dev/sdb
Press p to print the partition table to identify the number of partitions.
Press n to create a new primary partition.
Press p for primary.
Press 1 for the partition number, depending on the output of the partition table print.
Press Enter two times.
Press t to change the system's partition ID.
Press 3 to select the newly creation partition.
Type 8e to change the Hex Code of the partition for Linux LVM.
Press w to write the changes to the partition table.

Create new PV (Physical Volume) using following command:

# pvcreate /dev/sdb1

Verify the volume:

# pvs
# vgdisplay

Extend the volume group in a new partition:

# vgextend vg_root /dev/sdb1

This can also be used to span this volume across a second disk

Check the new size:

# vgs
# pvscan

Get the current available size and logical volume name using:

# vgdisplay
# lvdisplay

Increase the size of this logical volume using: (if the volume has already grown using all the space in the new disk, this is not required)

# lvextend -L +100G /dev/vg_root/vol1

In addition, it's required to increase the file system in this logical volume as well:

# resize2fs /dev/vg_root/vol1

Check the new current size used again size using:

# vgdisplay
# lvdisplay