Title
Virtual Machines By: Daniel Gilloch (dgilloch@learn.senecac.on.ca)
Introduction
The goal was to attempt to install a hypervisor on an already existing machine for our koji build farm and determine whether or not this would be a viable developement solution. Some issues taken into consideration:
- Cost
- Setup
- Performance
Approach
Determining and comparing the cost of buying arm machines, vs utilizing already existing hardware.
Determining the process of setting up virtual machines and the setup of an arm machine.
A Performance benchmark using koji build as this is a real world example of the exact type of developement that will be done on the machines. Also taken into consideration is if other environmental effects on the machine could interfer with build times.
Process
Cost
OpenRD-Base: 149.99
OpenRD-Client: 249.99
Q6600 Existing Machine: apprx, $700 CAD
Installation
Arm Emulation
The chosen hypervisor to run Fedora-ARM under Fedora was QEMU. QEMU was chosen over other hypervisors as it is a well known emulator that supports ARM platforms.
Libvert
Libvirt is a virtualization management framework and is full of useful tools. Libvirt provides tools such as “virsh” virtualization shell, as well as the “virt-manager” GUI tool that manipulates the command-line virtual machine management tools.
Installing and starting the virtualization software
yum groupinstall virtualization
yum install qemu-system-arm
service libvirtd start
Installing the ARM root filesystem and XML
cd /var/lib/libvirt/images
wget http://ftp.linux.org.uk/pub/linux/arm/fedora/qemu/zImage-versatile-2.6.24-rc7.armv5tel \
http://cdot.senecac.on.ca/arm/arm1.xml \
http://cdot.senecac.on.ca/arm/arm1.img.gz
gunzip arm1.img.gz
restorecon *
virsh define arm1.xml
Booting the Virtual Machine
Currently there seems to be an issue while running SELinux and Arm emulation under libvirt management. To bypass this problem, issue the command
“setenforce 0”.
The virtual machine should now be bootable and can be accessed using the virt-manager tool located (Applications>System Tools>Virtual Machine Manager)
Or from the command line: virsh start arm1
Alternatively, you can access the graphical display using the virt-viewer command: virt-viewer arm1
Creating Additional ARM Virtual Machines
In order to create additional ARM virtual machines:
Make a new copy of the arm1.img file under a different name in /var/lib/libvirt/images
Edit the XML, making the following changes:
1. Change the UUID (you can use uuidgen to generate a new one)
2. Change the image filename (in the source tag in the devices section) to point to the new image file you just created.
Use virsh define nameOfXMLFile to define the new VM from the modified XML file.
Performance In order to benchmark the virtual machines and the openrd client the most ideal situation was to run time along with building in koji as this is the intended purpose of the machines and virtual machines. I selected a package and built it multiple times on both the virtual machine and the openrd client to ensure consistancy. The Openrd client's results were very consistant at a build time of about 17 minutes, however the virtual machine's build times were sparatic. They ranged from 25 minutes to an hour depending on the work being done.
Discovery
What did you discover and learn during the process -- about the technology, the open source process, the community, yourself and your abilities, collaboration?