Servers

Testing Virtualisation Limits With A Network Training Laboratory

If you want to train large groups of students on how to use and deploy networking equipment, you’ll need to rapidly redeploy fresh system images as each new class comes in. That sounds like an obvious case for using virtualisation, but there are some traps to be aware of before pumping out those virtual machine images.

Labs picture from Shutterstock

During the server administration mini-conference at Linux.conf.au in Canberra today, James Lucas and Li Bing Chen explored some of the challenges involved in setting up virtualised network testing and training laboratory at the University of Technology Sydney (UTS). Those five labs are typically used for networking management courses (both full academic subjects and shorter certification courses), covering both specific hardware and broader concepts around networking, security and wireless. Each allows up to 30 students.

“In a typical setup, students will use a couple of machines, both Windows and Linux,” Lucas explained. “From those they’ll have physical networking connections to racks of networking equipment. The students need full access to all of these machines, These computers are internet connected but lab traffic must be kept off corporate networks as well.”

Having already used virtualisation to deploy Windows systems images in its general-use computer labs, UTS was keen to pursue a similar strategy for the training laboratories, rather than relying on error-prone messages such as swapping drives. However, there were some additional considerations. “When a student leaves a lab and the next one comes in, we need to be able to quickly reset the environments,” Lucas explained.

A particular challenge was ensuring that the virtualised environments could access physical wireless switches. That problem was solved by using PCI passthrough via IOMMU.

The big lesson? Virtualisation is a speedy method of deploying system images, but you need to check hardware support carefully. Also look closely at how rapidly you can roll out or migrate images, which can impact heavily on plans.

Lifehacker’s World Of Servers sees me travelling to conferences around Australia and around the globe in search of fresh insights into how server and infrastructure deployment is changing in the cloud era. This week, I’m in Canberra for Linux.conf.au, paying particular attention to the server administration mini-conference and sessions on virtualisation and best practice.