Private clouds vs. virtual servers

Virtualization and cloud computing expert Mark Bowker, an analyst at The Enterprise Strategy Group, explains to find out just how real companies' plans are for developing a private cloud. A private, or internal, cloud is a means of centralizing data center resources and delivering them on the fly as business demands change and IT attempts to become a service delivery unit to the company.

With server virtualization as its basis, cloud technology has a way to go, but CIOs are finding it a powerful vision. In part one of this two-part interview, Bowker offers insight into the differences between private clouds and virtual server farms and explains application awareness and the concept of a data center operating system. Part two will delve into specific CIO issues, including working with application owners to buy into a cloud strategy to make it a success.

Are people clear yet on what an internal cloud or private cloud is?
Bowker: The whole cloud definition is still very foggy, to say the least. You have companies like Cisco, VMware, Microsoft, Citrix and EMC all sharing cloud visions that are each a little bit different, but they're all driven around the same thing. [These vendors' strategies] are very centered on virtualization to make the cloud more of a reality. So once you virtualize things, such as your applications … then you have the sense that you can apply policies or service-level agreements directly to that virtualized infrastructure and that infrastructure will respond.

How is creating an internal cloud different from having virtual server farms?
Bowker: The difference is that the infrastructure you're building can actually respond. Storage and networking infrastructure is sharing its intelligence and knowledge with higher-level management technology. A specific example is that the network and storage would be able to take its intelligence and share it with VMware's vCenter, so that vCenter can see everything and policies can be applied to a workload, a virtual machine or throughout an entire infrastructure.

That's something that's not happening [in virtual server farms] today. You can move virtual machines between physical servers, but is the storage going to move? Is the security policy going to move? Is the networking going to respond or the bandwidth? Is all that going to move with the virtual machine? No.

So being able to move policies and resources within virtual server farms isn't happening yet?
Bowker: No isn't a very fair answer. In reality it's limited to where it's happening. It's taking the vendors working together to figure this all out. VMware or Microsoft is not going to go off and figure out how to make this happen. They have to work with the plumbing vendors … the storage and networking vendors. An example is how Cisco recently outlined its ecosystem, with Cisco providing the networking and server piece, EMC the storage infrastructure and VMware the virtualization layer on top that enables the management of that cloud.

How else is an internal cloud different from virtual server farms?
Bowker: What is also vision more than reality is the federation, universal control and management between internal virtualized infrastructures, or internal clouds, and external virtual infrastructures, or external clouds. So from an IT perspective, it's when I can move virtual machines between those two environments. I can use that other [external] site for disaster recovery purposes, for example, but now it gives me the option of not being confined by the four walls of my data center.

And you wouldn't have to work with an external cloud provider to do that?
Bowker: A provider is an option, but I could have a virtualized environment or external cloud running at a secondary site of my own. It makes the market for external providers interesting, but I think it's going to happen more so as companies own both sites, before it goes between a company owning one site and renting one site from a provider.

So there are still a lot of what ifs and the technology needs to mature, but are you seeing companies starting to develop private clouds?
Bowker: It's very early on. It's more of a vision. It has the potential of being the next step or value of virtualization, but there's a lot of missing pieces as well. Virtualization does some great things, but there are things that it doesn't address, either.

What doesn't virtualization address?
Bowker: An application today doesn't have awareness that it's running on a virtual machine. The operating system may, but what really matters is focusing on the applications. If I'm running Siebel, Oracle, PeopleSoft or SAP, that application needs to be made aware of the infrastructure it's running on.

If the application is aware that it's running in a virtualized environment ... I can actually span that workload across my computing environment. If you virtualize the entire data center, in VMware's terms you have a data center operating system. If that application is aware that it's running on a data center OS, there's a different availability policy I can apply, there's more flexibility in the way I can provide performance availability, bandwidth, security protection, etc. But if the application isn't aware, you still have to set that policy on a per-virtual machine level, not on an application level.