As features will undoubtedly continue to be added to OpenStack as it matures, news that Hyper-V support is dropped show that features can be taken away too. And with the news from Citrix this week, there could be some question of what that could mean for support for the XenServer in OpenStack, which is made by Citrix. Krishnan Subramanian, a blogger and researcher at says it would be "suicidal" for OpenStack to migrate away from Xen.
"It is in the interest of both Citrix and OpenStack that they work together on Xen hypervisor front," he says. "The VMware hypervisor support in OpenStack is also not mature because VMware is not officially supporting OpenStack." So, he says, OpenStack can't afford to lose XenServer support and support only KVM. McKenty, from Piston Cloud, says that is not at risk of happening. Rackspace uses Xen, so there is a community to support its functionality in OpenStack, he notes. Meanwhile, CloudStack backers are promoting their system as being "hyper-visor agnostic." In a response posted on a Network World article, Peder Ulander of Citrix writes that CloudStack supports KVM, OVM, XenServer and Hyper-V support is expected to come later this year.
Nonetheless, the Citrix news this week has highlighted some schisms between OpenStack and CloudStack, namely in the support for Amazon Web Services offerings. While OpenStack backers note that interoperability with AWS APIs is expanded in the compute and storage functions in the Essex release, CloudStack and Eucalyptus have taken a different approach. In announcing the Apache license for CloudStack, Citrix GM for cloud platforms Sameer Dholakia, made it clear that one of the major functions a Citrix cloud offering will be to have AWS compatibility. Eucalyptus and AWS's joint announcement solidifies their commitment to compatibility.
The open source cloud debate is clearly on, and it will continue to play out in the future. OpenStack and CloudStack officials have even both said their projects can coexist, and there may even be room for them to work with each other. Overall though the Citrix move ultimately means more players in the open source cloud game. And that is a good thing for end users, says Shawn Edmondson of rPath, a cloud services provider.
"More choice is a good thing in cloud stacks," he says. "With two strong open-source cloud stacks, we have competition to keep the contenders moving, but not the redundant effort and wheel-reinvention that would result from having too many stacks."