KVM - Creating Thinly Provisioned Guests

When you create external snapshots, you create a read-only file that represents your virtual machine at a certain point in time. Since the data is read-only, we can use this file as a base for other guests we create in future. In order to operate, the guests will have all…

Read this article

KVM External Snapshots

With external snapshots, a new file is created where all future changes are written to (the "delta" file), and the original file is stored in a read-only saved state. Advantages of External over Internal Much faster creation (creating an empty file to store future data and setting up links). Can…

Read this article

KVM - NUMA Declaration

Computers can have more than one system bus which allows them to have multiple processors in a single system like the one shown below: This allows the servers to achieve higher compute capability at a better price to performance ratio, or to just exceed the possible compute power limitations of…

Read this article

Cloning CentOS Guests - Disable MAC

Today I was scratching my head trying to figure out why my changes to the network to go from DHCP to static IP was not taking effect on my CentOS 7 guest. It turns out that the network configuration is defaulted to including the HWADDR (MAC) address as shown below:…

Read this article

Debian 8 KVM Guests - Get The Console Back

It appears that Debian 8 guests boot up without console access by default in KVM. To fix the issue read the solution I posted on Unix & Linux.…

Read this article

KVM - Add Disk

I run my virtual machines on SSD storage which is expensive compared to traditional HDD storage. Thus if a virtual machine needs a lot of storage, such as for a mirror, then I will give it an HDD disk to put the data on. Here's how to do just that.…

Read this article

KVM Cheatsheet

List Running Virtual Machines virsh list List All Virtual Machines virsh list --all Managing Guest State Shutdown Guest virsh shutdown $VM_ID_OR_NAME Start Guest virsh start $VM_ID_OR_NAME Reboot Guest virsh reboot $VM_ID_OR_NAME Destroy a Guest This command is an ungraceful shutdown, much…

Read this article

Qcow2 Conversion and Snapshotting

If you use Virtual machines, such as within KVM, then you may be running raw disk images. Converting them to Qcow2 will give you some advantages, such as the ability to snapshot your VM. Here we will show you how to: Check your disk file's format to see if it…

Read this article

Ubuntu 14.04 - Getting Started with KVM using PHP Helper Script

This post carries on from my previous article on how to install KVM on Ubuntu 14.04. To make life easier, I have created a PHP script to dynamically generate the KVM commands you need in order to create guests. Run these commands to install the PHP CLI package and…

Read this article

KVM Resources

This page is dedicated to all of the useful articles I have found on the net for using KVM. KVM Installation How To Geek - How to Install KVM and Create Virtual Machines on Ubuntu Ubuntu Docs - KVM Installation CentOS Docs - Create a guest using virt-install HowtoForge -…

Read this article