Simon Gallagher needed a place to study for his VMware certification exams, where he could test his virtualisation chops without breaking the bank.
Having worked in IT for 15 years, Gallagher said he has always used a test kit. But this time he decided to get serious and build a VMware home lab to aid with some hands-on, personal virtualisation certification training. Gallagher designed the home lab mainly to study for his VMware Certified Professional 4 (VCP4) exam, which he passed.
"I can use and test all of [VMware's] Distributed Resource Scheduling [DRS] and High Availability [HA] features, simulating a large production environment," Gallagher noted. "And it allows me to run through upgrade scenarios from vSphere 4.0 to 4.1 and patching."
Dubbed vTARDIS (Transportable Awfully Revolutionary Data Centre of Invisible Servers), his project recently won in the Best of Show and Best Remote-Office/Home-Office Virtualisation Project categories at the VMworld Europe 2010 User Awards.
At the geek cabin
Gallagher wanted access to a multinode ESX cluster, with all the enterprise-level features, so he could really experiment. Doing this with physical equipment would have been costly, so Gallagher began by researching how to run VMware ESX server as a virtual machine (VM), a tactic known as nesting. From there, he set out to build the lowest-cost but most capable home-lab environment he could on a single PC. Also, the lab had to be quiet because he planned to leave it on 24/7 at home.
It appeals to my inner geek.
Simon Gallagher on his award-winning project,
"I've always had a lot of kits at home, and it was getting ridiculous, the amount of servers that were collecting spiders in my garage. Most of the project, however, came out of my own pocket, so I needed to find the cheapest way to build the lab with all the features and capabilities I needed to study," said Gallagher.
With a Hewlett-Packard Co. ML115 G5 with only 8 GB of physical RAM and 128 GB of solid-state disk (SSD), Gallagher built an eight-node VMware vSphere 4.0 cluster with an iSCSI storage area network and 60 nested VMs, on a single PC-grade server. This enabled him to practice managing a larger cluster whilst learning the principles of shared storage, VMware HA, DRS and Fault Tolerance. It also allowed him to run complex PowerShell scripts on the cluster for management. The project also enlists third-party tools, such as Openfiler for the storage layer and Vyatta Core for the firewall.
The challenges of vTARDIS
Gallagher started with SATA disks, however, "Disk bottle neck was always a problem for me," he said.
To solve this issue, he moved to SSDs to reduce disk I/O. Coupled with the "nested" VMware ESX VMs, this gave the appearance of owning many ESX hosts even though the entire infrastructure sits on just one physical box.
When vTARDIS runs all its nested VMs, it enables Gallagher to use and test critical virtualisation features and simulate a large production environment and vSphere upgrade scenarios, which are all critical for VMware certification training.
"The current box took about a year and a half to build. It appeals to my inner geek, as it's doing something pretty mind-bending in running VMs inside another VM, inside another VM," Gallagher said.
Behind the vTARDIS moniker
The envelope-pushing project also incorporates a bit of humour. The moniker vTARDIS is a play on the BBC TV series Dr. Who, where the protagonist uses a time-travelling machine that is much larger on the inside than on the outside. In his project, Gallagher runs more servers on the inside of the box than there are physical servers.
Gallagher is already back to work on improving and upgrading the original vTARDIS to include support for VMware's vCloud Director, the virtualisation provider's cloud offering for private and hybrid clouds.
For all the news and coverage from VMworld Europe 2010, click here.
Kayleigh Bateman is the Site Editor of SearchVirtualDataCentre.co.UK.