Category Icon

CentOS Images

Pre-built CentOS images for rapid deployment in cloud environments for easy deployment of nodes from a master image.

Working with Virtual Machine images

CatN engineers spend a lot of time working with virtual machine images. We have put together this useful list of commonly used commands and procedures to help you get started on your next project.

For simplicity we assume to work with VM images created using the shell script, as explained on my previous post “Automated CentOS Virtual Machine Image Creation”.

Read More

Add a virtual storage device to a Virtual Machine

Following our previous article about resizing virtual machine images, we now look adding an additional storage device to an existing VM. If instead you wish to extend the existing VM storage volumes, please consult the article “Resize a CentOS Virtual Machine Image“.

For simplicity we assume that the VM image you wish to extend has been created using the shell script, as explained on my previous post “Automated CentOS Virtual Machine Image Creation“.

The file-based virtual storage device acts as a virtualized hard drive for virtualized guests and its creation is quite quite straightforward.

Read More

Resize a CentOS Virtual Machine Image

Following our series of articles about virtual machine images, we now look at a common problem faced by system engineers – what happens when you run out of disk space on your virtual machine? This guide addresses this issue and explains how to expand a CentOS Virtual Machine image, resizing any partitions contained within.

We assume that the VM image to resize has been created using the shell script, as explained on my previous post “Automated CentOS Virtual Machine Image Creation“. This is because the resizing script ( assumes details about storage volumes that rely on the having be used. In any case all the steps are illustrated here so you can adapt the commands to your needs.

The shell script is part of the CentOS-KVM-Image-Tools project that you can clone on your machine using the following command:

git clone git://

Read More

Automated CentOS Virtual Machine Image Creation

This article shows how to create a CentOS Virtual Machine (VM) in unattended mode using a shell script and illustrates the main steps and options to reproduce the process manually.

The following script and commands will create a base image that can be used to deploy multiple nodes from a system like Ansible to define roles for each node. It is very useful for creating clustered virtual environments such as the vCluster stack.

Read More

Building a virtual machine image for CentOS

CentOS Images Featured Header

This post describes the process of creating a CentOS virtual machine image. Creating a base or master image is incredibly useful in a cloud environment as it allows the creation of multiple nodes / VMs or guests based on the original template.

We have an existing CatN Labs project where we are hosting pre-built CentOS golden master images for use when deploying multiple nodes. You can read about the project on the CatN Labs CentOS Images page.

The base image is a static template of software including OS which is mounted when the VM runs and referenced by further clone nodes. To get started on the base template you will need to have some tools installed on your Linux node. Adapt the following commands for your distribution of choice!

Read More