PT CEMERLANG DIGITAL TECHINDO
EXPAND DISK LVM UBUNTU FROM 2 DISK (SDA & SDB
EXPAND DISK LVM UBUNTU FROM 2 DISK (SDA & SDB
admin
May 25, 2026
1:30 pm

Expand LVM on Ubuntu Using 2 Disks (sda & sdb)

Logical Volume Manager (LVM) on Ubuntu allows administrators to expand storage dynamically without reinstalling the operating system.
In this scenario, the system already uses /dev/sda, and a second disk /dev/sdb is added to increase storage capacity.

What is LVM?

LVM (Logical Volume Manager) is a storage management system in Linux that provides flexible disk management.

LVM consists of:

  • PV (Physical Volume) → Physical disks or partitions
  • VG (Volume Group) → Combined storage pool
  • LV (Logical Volume) → Virtual partitions used by the filesystem

Expansion Process Overview

Before Expansion

  • /dev/sda contains the existing LVM storage.
  • The root partition is nearly full.

After Expansion

  • /dev/sdb is added into the existing Volume Group.
  • The Logical Volume size increases.
  • The filesystem is expanded to use the new space.

Step-by-Step Process

1. Check Current LVM Status

lsblk
sudo pvs
sudo vgs
sudo lvs

These commands display disks, physical volumes, volume groups, and logical volumes.

2. Prepare the New Disk (/dev/sdb)

Create a new partition and configure it for LVM.

sudo fdisk /dev/sdb

Inside fdisk:

  • Create a new partition
  • Set partition type to 8e (Linux LVM)
  • Save changes

Then refresh partition information:

sudo partprobe /dev/sdb

3. Create a Physical Volume

sudo pvcreate /dev/sdb1

This converts the new partition into an LVM Physical Volume.

4. Extend the Volume Group

sudo vgextend vg0 /dev/sdb1

This adds /dev/sdb1 into the existing Volume Group vg0.

5. Extend the Logical Volume

sudo lvextend -l +100%FREE /dev/vg0/root

This allocates all available free space to the root logical volume.

6. Resize the Filesystem

For EXT4 filesystem:

sudo resize2fs /dev/vg0/root

For XFS filesystem:

sudo xfs_growfs /

This step allows the operating system to use the newly expanded storage.

Verify the Expansion

df -h
sudo vgs
sudo lvs

These commands confirm the new storage size.

Benefits of Using LVM

  • Easy disk expansion
  • Flexible storage management
  • Minimal downtime
  • Better scalability
  • Simplified server administration

Important Notes

  • Always back up important data before modifying partitions.
  • Ensure the new disk is healthy and detected properly.
  • Verify filesystem type before resizing.
  • Use correct VG and LV names based on your environment.
Category : Uncategorized