The OpenStack conference 2012 is full of OpenStack fans, aficionados, developers, and companies making a business using the ecosystem. However, I kept hearing that OpenStack was a replacement for VMware. So why is this even a possibility, and why did Rackspace and now HP build public clouds using this technology? The easy answer is to save money. But is that the only answer? What is OpenStack and why is it becoming important?Let’s start by saying that OpenStack is not a product you can buy. It is:
- A Cloud Framework
- A Cloud Control Layer
- An Object Store
So why is it seen as a replacement for VMware, and what do they mean when they say this? Initially, I thought OpenStack distributions were a replacement for just VMware vCloud Director, and in many ways it is just that. It provides the command and control necessary to build multi-tenant cloud instances, but it has more than that, it also contains an object store that can be used by Applications that need access to large amounts of scalable storage.
So does this mean that OpenStack is also a PaaS Play? No it is not a PaaS play, while a PaaS may eventually become part of OpenStack, or PaaS products may be built on top of an OpenStack framework, it is not a PaaS play. But it has an object store? Which is ideally suited for building cloud based applications.
It may be better to look at the OpenStack Framework as two different cloud offerings within one framework:
- Cloud Storage
- Cloud Control
Most clouds based on OpenStack also make use of other open source components such as KVM or Xen as their hypervisor layers, and use ingenious storage solutions to provide redundancy and features not already found in those hypervisors: such as Storage vMotion. In essence, the hypervisor is good-enough to do the job given that the surrounding architecture handles the lack of higher-end functionality. In addition, application design for placement in the cloud also alleviates the need for such tools as storage vMotion and storage IO Control within OpenStack based clouds.
There are two public clouds using OpenStack: HP Cloud Services and Rackspace. Rackspace has been using OpenStack for their offering for years, while HP Cloud Services is relatively new to OpenStack and will be involved in future governance. Rackspace currently provides the technical and political leadership behind OpenStack but that will be changing shortly to the governance by the Openstack Foundation. Rackspace will remain involved, with 8 other platinum level sponsors, 8 gold level sponsors, and 8 members of the community at large.
In essence, OpenStack is a framework within which a cloud offering can be created using all or one of the OpenStack components; distributions can be made to stand up your own Cloud offering such as from StackOps and Piston Cloud Computing; or a cloud in a rack such as mCloud from Morphlabs. Is it a replacement for VMware? To some, it is, but only if the proper cloud architectures is in use. The reason it may not be, is you can put the OpenStack bits on top of VMware vSphere. Yet, the current offerings around the OpenStack community do not use vSphere under the hood. Instead they use either OpenSource Xen or KVM.
In the end, it is a cost issue.