The OpenStack open source cloud platform has a major e-commerce backer in its corner, now that eBay’s gone public with details of its implementation, as InfoWorld reports. Of special note: Even though eBay is using OpenStack specifically as an exit strategy from the VMware ecosystem, the auction site is using Nicira – recently acquired by VMware for $1.26 billion – for network virtualization.

As InfoWorld reports, eBay is using OpenStack for “a high-volume dev, test, and experimentation environment where apps are created for eBay Marketplaces.” And while eBay’s use is fairly minimal at the moment, we can expect their implementation to scale up as the platform matures.

Nicira’s technology, which also forms the core of the OpenStack Quantum virtual networking project, enables eBay to spin up isolated networks on a per-app basis, scaling up to “hundreds” of projects. VLANs just weren’t scalable enough – it had to be software-defined networking. And even if VMware does cut Nicira’s contributions to the OpenStack Quantum project, the fact that they have so many APIs in common means that migration and implementing new Quantum features should be a relative snap.

“We wanted to have a fabric that was shared. Instead of physical environments, we wanted to have virtual environments on top of that fabric. And in order to do that, we wanted to have network isolation,” eBay cloud architect Jean-Christophe Martin told Infoworld.

As for why OpenStack itself, it’s part of a strategy to move from a locked-in environment – cough, VMware vCloud, cough – into one where any component of the stack, be it hardware of software, can be switched out at whim. And using KVM for the hypervisor is apparently a major part of that approach, as eBay tries to build a bridge out from VMware’s licensing scheme and roll something that can run on commodity hardware.

“Really, our focus was an alternative to vCenter. So we have now vCenter on ESX and OpenStack on KVM that provides almost the same capability. That’s definitely one of our new strategies. Before, we were mostly looking at vendor-provided solutions. I think that right now we are switching to more of an open source strategy,” Martin says.

As of the last OpenStack Design Summit in San Francisco, there was some vocal concern that large users hadn’t started talking about their deployments yet – customers are the only metric of platform success that matter, and while eBay was represented at the event, it was still fairly vague on its implementation. If eBay is willing to speak up, that speaks well for OpenStack’s maturity, which is especially important as it’s repeatedly called into question.