How to Create Virtual Machine Snapshots Using LVM

When experimenting with clusters or load‑balancing, creating many virtual machines manually is inefficient, so this tutorial shows how to use LVM snapshots to quickly produce VM instances.

1. Create logical volumes:

fdisk /dev/sda partx -d /dev/sda partx -a /dev/sda pvcreate /dev/sda vgcreate -s 4M vg1 /dev/sda5 lvcreate -L 10G -n base vg1

These commands set up the physical volume, volume group, and a 10 GB logical volume that will serve as the VM template.

2. Build the VM template: Install the operating system on the logical volume, then customize it for reuse.

3. Prepare the template for cloning:

Disable firewall and SELinux:

vim /etc/sysconfig/selinux

Adjust network configuration and remove specific NIC settings:

vim /etc/sysconfig/network-script/ifcfg-eth0

Replace the yum repository with a stable source:

vim /etc/yum.repos.d/yum.repo

After these modifications, shut down the VM so the template is in a clean state.

4. Create the snapshot: Use the LVM snapshot feature to capture the template’s state. The snapshot can then be cloned to launch new VMs instantly, each requiring only about 4 GB of additional space.

By following these steps, you can produce many virtual machines from a single template, greatly reducing installation time and storage overhead.