We’ve recently been running into a problem with our virtualization infrastructure that I found a solution to in Microsoft Hyper-V: VLAN Tagging.

For our main virtualization infrastructure, we are using HP C-class Blades with 4 NICs, each connected to a different VLAN. These servers are set up as a cluster and this has significantly limited our abilities to virtualize more servers than we have, due to the limited number of VLANs we can connect the cluster to for the guest VMs.

Enter Hyper-V with the ability to do VLAN tagging at the VM level. Now, I can trunk the four connections together to provide redundancy and additional throughput for my bandwidth hungry VMs, assign them to multiple VLANs, and have the VMs tag the VLAN they belong on. Sounds simple but obviously there is a lot of planning and configuration that goes into this, especially in a clustered & complex environment such as ours.

I will be posting a follow-up post with step-by-step instructions for how to do this on a more basic level, but the fundamentals will apply to more complex scenarios.