I’ve written about VXLAN before: it’s a proposed technology to tunnel frames over an existing IP network, allowing for much more than the 4096 VLAN limit. When writing that article, an RFC draft was proposed, which expires this month.

Coincidentally or not, Cisco has just released some new switching products, among which a new version of the Nexus 1000V, which claims to support VXLAN. Given the recent release of IBM’s 5000V virtual switch for VMware products, we’re seeing a lot of innovation done in this market segment lately, and it will surely not be the last. As I have yet to test a NX1000V, I’m unsure what VXLAN support means in real life, how it will impact network topologies, and what issues may arise. Two things stand out very clear to me: VXLAN (or any other tunneling over IP) introduces an extra layer of complexity in the network, but at the same time, it allows you to be more flexible with existing layer 2 and layer 3 boundaries as VXLAN does not require any virtual machines to be in the same (physical) VLAN for broadcast-related things, like vMotion for example.

I do have doubts that at this point in time there is a lot of interest towards these products. vSphere and competitors are delivered with a vSwitch present, so it’s less likely to be invested in: ‘There already is a switch, why place a new one?’. But the market is maturing and eventually, vSwitch functionality will become important for any data center.

Also, last but not least, special thanks to Ivan Pepelnjak and Scott Lowe. They both have excellent blogs with plenty of data center related topics, and I often read new technologies first on their blogs before anything else.