In-Depth

Azure Stack: Microsoft’s Cloud Technology for the Datacenter

The option for Windows Server 2016 that will let enterprises and hosting providers build private clouds based onthe same technology as the Azure service is now available to testers to evaluate. Some say it could bring major changes to the datacenter.

• By Jeffrey Schwartz
• 05/05/2016

The forthcoming release of Windows Server 2016 will represent Microsoft's boldest effort yet to transform its server OS into a Cloud OS. If that sounds familiar, it's because that was the theme of Windows Server 2012 when Microsoft launched it four years ago. Did Microsoft overstate Windows Server 2012 as a Cloud OS at the time? That depends on your view of the public Azure service both then and now. Perhaps the Windows Azure Pack (WAP), which introduced an Azure-like experience during the Windows Server 2012 time frame, was an exaggeration from the pure sense of providing a common platform. Certainly, the WAP introduced the concept of building private clouds, and some claim it suits many organizations today. Others argue that WAP didn't mimic the true public Azure cloud. Instead, it emulated Azure within a private environment but it was effectively providing an overlay atop Windows Server 2012.

"Rather than trying to run Azure bits on-premises, it used a UI experience similar to that of Azure Portal (classic) to manage on-premises resources," wrote Microsoft Azure MVP Vishwas Lele, chief technology officer at Applied Information Services in Reston, Va., and a Microsoft Regional Director, in a blog post. "However, the notion of first-class software-defined storage or software-defined networking did not yet exist. Finally, WAP only made available one PaaS [Platform-as-a-Service] offering, the Azure Pack WebSites -- a technology that made it possible to host high-density Web sites on-premises. The fact that other Azure PaaS offerings were not part of WAP was also a bit limiting."

Many of those limitations go away with Azure Stack, according to Microsoft and affirmed by those who've tested the first bits that the company released. "We are taking literally the Azure code and making it available on-premises," said Microsoft Technical Fellow and Lead Architect for the Enterprise Cloud Group Jeffrey Snover in a Channel 9 video describing Azure Stack.

A Common Public-Private Cloud Platform
Snover was joined by Mark Russinovich, CTO of Microsoft Azure, who explained that providing that same experience is important because developers can build applications to run on Azure Stack in the datacenter and those same applications can run in the Azure public cloud with third-party hosting providers using the same APIs and SDKs. "It's about bringing the consistency of the hyperscale public cloud Azure platform to your own datacenter, about enabling your developers to create the applications that will run in both places, about enabling your end users to interact with those applications in the same way in both environments," Russinovich said.

Azure Stack is scheduled to arrive before the end of the year, though many details remain unclear, such as whether Microsoft will offer it as an optional Windows Server 2016 SKU or as a separate add-on. In short, Azure Stack with Windows Server 2016 will let enterprises and services providers run the same Azure in their own datacenters as Microsoft operates in its public cloud.

Azure Resource Manager -- Common Control Plane
The recent implementation of the Azure Resource Manager (ARM) in Microsoft's public cloud provides a common control plane among the 59 core Azure services, where all resources and their interdependent parts are now part of a single entity. That will bring powerful capabilities to Azure Stack, too, Russinovich said, such as for template-based deployment of applications that may utilize various resources, including Web sites, databases and, perhaps, cache. Those apps can be deployed in an enterprise marketplace or gallery, as well as in the public Azure marketplace. "Developers can create these things, and users can deploy them with a few clicks, parameterize their configurations specific to their deployments and within minutes they have that complex application up and running," Russinovich said.

Through the ARM common control plane, applications have role-based access control (RBAC), Russinovich added. "So with both Azure and Azure Stack you can use Azure Active Directory roles and user assignments to give users appropriate access to the resources that their applications need and that all enforce as a common way across all Azure services using Azure Resource Manager," he explained. "With this kind of model, you can take a template, develop an application on-premises, then take that same template and deploy it in the cloud or, vice versa, take an application and decompose it into multiple templates, part of the application in the cloud, part on-premises, and have a unified role-based access control model across all those environments."

The portability aspect of Azure Stack is important because developers and IT pros can extend their programming and management skills. "All of the PowerShell cmdlets in the Azure CLI, which works on Mac and Linux, you simply point it at Azure Stack or Azure public cloud and the same APIs and cmdlets work," Snover said, adding it supports other popular DevOps tools such as Ansible, Chef and Puppet. "You can hire more people with the same skillset and make them more productive with less training."

Enterprise Potential
The notion of running Microsoft's Azure cloud in their own datacenters is very appealing to high-level decision makers at some of the largest banks, health-care providers and government agencies, says Rand Morimoto, a Microsoft Azure MVP and president of Walnut Creek, Calif.-based Convergent Computing, which provides IT development and deployment services. Morimoto says many of his large enterprise clients won't move their systems into the public cloud due to concerns about security and performance, but they want to move to a cloud platform.

Like others interviewed about their early experience with the Azure Stack Technical Preview, Morimoto notes that testers can only run one virtual machine (VM). Nevertheless, Morimoto and his colleagues like what they've seen so far. "The infrastructure pieces such as a Windows VM or setting up a virtual appliance running a Linux VM, all of this stuff is 100 percent," he says. "We've yet to find anything that I can run in Azure public as an IaaS [Infrastructure-as-a-Service] VM, that I can't run on-premises. And the folks we are doing Web apps and SQL with are also identical."

Beefy Hardware Requirements
Testers are advised by Microsoft to deploy the Azure Stack Technical Preview on a dual-socket server with 16 physical cores with 128GB of RAM and at least a terabyte of storage running on four disk drives. Microsoft has published minimum and recommended hardware.

During a workshop at the recent TechMentor conference in Las Vegas, which, like Redmond magazine, is produced by 1105 Media Inc., Clint Wyckoff, Microsoft Cloud and Datacenter MVP, and Hyper-V MVP and consultant Dave Kawula installed Azure Stack. "It's a long process to say the least," said Wyckoff, who is also a technical evangelist at data protection software vendor Veeam Software. "It takes a while to actually go in and deploy all of the virtual machines and get everything from the virtual network and the domain controllers and everything completely set up." Wyckoff said once installed, attendees were impressed with what they saw. "Azure Stack is 100 percent the exact same experience that people are familiar with in the public Azure," he says. "The look, the smell, the feel, the clicks, the blades, everything of Azure Stack is what people are used to using in their public Azure subscription." Despite some of the limitations of WAP with Windows Server 2012/R2, Morimoto believes its VM model is still suitable for smaller shops that want to run apps in a cloud style and will remain so even as some deploy Windows Server 2016.

"I don't see Azure Stack replacing what Windows Server 2012 set out to do for the private cloud, for the small organization, for custom or internal systems," he says. "Azure Stack addresses the larger scale and it has a completely different model. When we look at the way Azure Stack is architected, it's based on cores, not virtual machines, and that's a big thing for customers."

The reason it's big, he explained, is because it means rewriting an application, giving it the ability to scale infinitely. Case in point, Morimoto recalls a conversation he just had with a client who wants to move a SQL application to Azure Stack. "Their idea is move their eight SQL servers into VMs, which most certainly they can do and that's going to be phase one to the cloud," Morimoto says. "But the whole idea is take that SQL application and rewrite it into [PaaS], and that way I'm not riding on VMs. I can scale infinitely just by selecting how many PaaS cores I want. It's a rethinking."

IT people are having a hard time with this, he says, because many still don't completely understand the difference between an Azure Stack by resources or cores, versus VMs. "It's going to take two to three years for customers to educate themselves on how this works," Morimoto says. "For those who are jumping in, the way we're jumping in with [IaaS] as a first step."

In the second phase, Morimoto says his consultants are creating proofs of concept that involve the recoding of their applications from running them as VMs on an infrastructure into PaaS. "Once a customer gets to that point, you're just moving your SQL table into a SQL environment where all you're worrying about are your SQL rows and columns and tables and cubes, and there's no underlying operating system or anything else to manage," he says.

Third-Party Azure Providers
Morimoto believes Azure Stack will initially only make sense for the largest of enterprises and says the most likely early adopters will be hosting and services providers. Indeed, Microsoft is bullish that a huge network of cloud services providers will deploy Azure Stack, offering it as an alternative or in tandem with its own Azure service. As that provider network emerges, organizations will either run all of their applications on Azure clouds operated by Microsoft or any number of Azure services providers, as well as those who have internal Azure Stack-based datacenters.

"We expect to have hundreds of service providers to take Azure Stack and offer Azure as a service across the globe," Snover said. "Then as customers deploy that, we expect thousands of enterprises to be running Azure in their own datacenters. So you will be able to get Azure anywhere you want with this fantastic vibrant ecosystem."

Emil Sayegh, CEO of services provider Codero, which offers cloud services based on CloudStack, says his company passed on the earlier WAP offering because he felt it wasn't services-provider-friendly. Given the limited deployment option with the early technical preview of Azure Stack, it's hard to draw any firm conclusions, but Sayegh says he's encouraged by what he's seen. "We did look at it but did not deploy it or do extensive testing," he says. "We're just wanting to wait and see how all of it progresses. We're cautiously optimistic. We're encouraging Microsoft that this is the right direction and to keep moving."

"We're cautiously optimistic. We're encouraging Microsoft that this is the right direction and to keep moving."

Emil Sayegh, CEO, Codero

Eric Brinkman, a product manager at Chicago-based Hostway Services Inc., which offers a virtual private cloud running WAP to service all of its customers, has spent time testing Azure Stack and welcomes the new capabilities it will bring.

"We have many customers running an environment with Windows Azure Pack and they're happy with the functionality that's provided to them," Brinkman says. "Windows Azure Pack is an awesome product but limited in functionality in terms of bringing all of the feature sets available from Azure public cloud proper to an on-premises datacenter. Azure is going to bring more of those features to the private cloud world. In my opinion, when you look at Microsoft and [Amazon Web Services] and Google, the big thing that differentiates Azure from the others is having a true hybrid on-premises story."

Rackspace started testing the Azure Stack preview as soon as it first became available and plans to have an offering based on the new platform at launch, says Jeff DeVerter, chief technologist for the company's Microsoft practice. Like others, DeVerter says it's too soon to determine Azure Stack's full capabilities, given the limitations of the early preview, but so far he says it's encouraging. Like Hostway, Rackspace offers WAP-based cloud hosting.

"I'll call it a fulfillment of the promise they made with Windows Azure Pack with Azure Stack running the same code base, running the same APIs," he says. "Despite the limited feature set, Azure Stack gives a company like Rackspace the ability to provide that truly in-Azure experience for a customer in a truly private environment, being able to dedicate and isolate them from the network, to the compute, down to the storage, which is what they really want."