Google and VMware are clashing over private clouds, and the question of whether customers benefit more from building highly virtualized data centers inside their own firewalls or from outsourcing IT needs to public cloud providers such as Google and Amazon.
VMware is trying to convince enterprises to use its new cloud operating system, a software layer that virtualizes and aggregates servers and storage into one computing pool, making it easier to manage internal data center resources and provision new services to users.
Google took a swipe at VMware's approach with an official blog post on April 28 titled "What we talk about when we talk about cloud computing." Google doesn't mention VMware by name, but the blog post downplays the benefits of using virtualization to build private clouds, and was published after VMware's private cloud announcement.
"There's quite a bit of talk these days about corporations building a 'private cloud' with concepts like virtualization, and there can be significant benefits to this approach," writes Google Apps senior product manager Rajen Sheth. "But those advantages are amplified greatly when customers use applications in the scalable data centers provided by companies like Google, Amazon, Salesforce.com and soon, Microsoft."
Some industry experts have contended that cloud computing cannot exist without virtualization. If true, that contention would certainly benefit VMware's business. But Google officials have said they do not virtualize production hardware and instead use a job scheduling system of Google's own design to manage its many thousands of servers.
Google's approach is the one best suited to providing businesses the scalability and cost-efficiency they need, Sheth contends. The public cloud doesn't have to be limited to small business customers, either, he writes, saying that the model's "advantages in cost and innovation continue to attract hundreds of thousands of companies of all sizes."
"In the virtualization approach of private data centers, a company takes a server and subdivides it into many servers to increase efficiency," Sheth writes. "We do the opposite by taking a large set of low-cost commodity systems and tying them together into one large supercomputer. ... Enterprise hardware components are designed to be very reliable, but they can never be 100% reliable, so enterprises spend a lot of time and money on maintenance. In contrast, we expect the hardware to fail, and design for reliability in the software such that, when the hardware does fail, customers are just shifted to another server."
VMware has taken exception to Google's blog posting, saying Google's approach works for the limited set of applications that Google delivers, but it can't provide the level of functionality most enterprises are looking for.
"If you take a very narrow view of the world that says 'I just have a couple of applications I need to do - search, online advertising, Web applications - sure, you don't necessarily have to virtualize," says Dan Chu, VMware's vice president of emerging markets. "Sure, you can take a very custom way of [delivering a few applications] but that has nothing to do with the business and enterprise world we all know."
Chu has responded to Google with a blog post of his own, which VMware says it will post Tuesday.
Chu's blog says that VMware, like Google, ties data center resources together into "one large supercomputer," but that it does so for individual customers, and provides connectivity to the services of cloud providers. This gives businesses consistent management over internal and external resources, and doesn't limit them to using Google-built applications, Chu writes. With features like live migration of virtual servers and storage, and high availability and fault tolerance, VMware customers can achieve the levels of business continuity and availability that Google is boasting of, he writes.
While Google argues that customers should use Gmail instead of running virtualized instances of Exchange inside their own data centers, Chu responds that Gmail is not ready for the enterprise.
"Enterprises aren't going to move off an enterprise class mail platform for a personal-use platform," Chu writes. "Exchange ... represents the kind of business-critical core IT application that ... customers want running on VMware today."
Google, obviously, is not a VMware customer. Neither is Amazon, which uses the Xen hypervisor. This is one of the limitations of VMware's approach to building public-private hybrid clouds - it only works if the cloud vendor is using VMware. But there are more than 500 service providers partnering with VMware on this front, including major ones such as AT&T, Savvis and Terremark.
While VMware touts the ability to use both private and public data center resources, Google's Sheth argues that the private data center is plagued by management hassles and a slow pace of innovation that relies on the two- or three-year release cycle of software vendors.
"In our model, we can deliver innovation quickly without IT admins needing to manage upgrades themselves," Sheth writes. "As companies weigh private data centers vs. scalable clouds, they should ask a simple question: Can I find the same economics, ease of maintenance, and pace of innovation that is inherent in the cloud?"
Sheth also touts Google App Engine, which lets customers deploy applications on the Google cloud without having to worry about purchasing and maintaining their own servers and databases.
VMware contends that the App Engine simply isn't robust enough for an enterprise to run its core applications.
"For customers looking to maintain the flexibility to move back and forth between the external cloud and internal IT, Google's proprietary platform is like the Hotel California or the roach motel, where your apps go in, but they never come out," Chu writes.