Windows Azure Appliance – Your private corner of the Microsoft cloud

The “private cloud” concept (i.e. the idea of running the cloud-designed applications on your premises) can be implemented in a variety of ways. Not surprisingly, each cloud vendor also provides its own notion of “private cloud”. Now Microsoft adds yet another approach to the mix by launching Windows Azure Appliance.

Before looking into the appliance launch made yesterday in WPC10, I’ll provide a short backgrounder on the cloud, private cloud and the different XaaS approaches. If you just want to read about the launch, skip ahead!

What is private cloud?

Private cloud could be defined as the cloud-level infrastructure implemented in an enterprise setting. Perhaps the simplest example is the one often used with VMware products: Instead of buying a bunch of servers for a specific purpose, you buy a stack of general-purpose servers, assign them into a massive pool and start dividing out the resources (computing power, storage, …) to the various purposes within your organization.

The key levers to this are automated management and the virtualization. These advances allow reasonably sized pools of computers to act with a cloud-like elasticity, providing fault tolerance and scalability on-demand. Thus, the role of IT operations change: They become more like a service provider, perhaps with less exact control over the applications running in the datacenter.

The different levels of service

The virtualization-based level of abstraction from the cloud is typically called IaaS, Infrastructure as a Service. In an IaaS setting, the application is a normal Windows, Linux or whatever application – it just runs on servers virtualized in a specific way. The virtualization environment could be your local Hyper-V or VMware installation, but it could also be a cloud provider such as Amazon EC2.

It is a reasonably simple notion when compared to PaaS, Platform as a Service, which Windows Azure mostly represents. With a PaaS application such as a Windows Azure Web Role, the software is specifically built for the service platform. In exchange for requiring a slightly different development skill set, the PaaS platform hides the complexity of scale and fault tolerance. For example, a failure of a Windows Azure server is transparent to the application. Likewise, an Azure application can be scaled to thousands of computers without code changes – if the Azure programming paradigm has been duly followed.

Above both these is the notion of SaaS, Software as a Service. The users of SaaS applications are the end users – they don’t want a platform, they just want an application that works for their purpose. Typical offerings include Google Apps (email, document sharing etc.), Microsoft Business Productivity Online Suite (likewise), (CRM) and so on.

Note that all these XaaS offerings are layers upon one another. There is no grading here: one is not better than the other, nor does one represent an advance over the others. What works for you depends on your needs.

What is the Windows Azure Platform Appliance?

Essentially, it is a container of about a thousand servers, deployed on your own premises. You can’t touch the inside though – just plug in lots of electricity, cooling and network capacity, and you’re good to go. What runs inside is the same application platform as in the public Azure cloud.

The key point is that the software platform is managed by Microsoft. When Windows Azure gains new capabilities, the software inside your container will be upgraded. And although you’re in charge of the schedule, you don’t need to – and you can’t – touch the actual upgrade process.

This is what separates the Appliance from various other private cloud offerings. For example, VMware’s notion of a private cloud mostly revolves around the idea of getting cloud technology to run on-site. Microsoft now extends this notion by bringing the service into the on-premise datacenters. The Azure Appliance is not just the platform on-premises, it is the platform service on-premises.

So far, it has been promised that the appliance will be running both Windows Azure and SQL Azure. This means that it will be a sufficient platform for most cloud-based application that can be currently run on the public Azure cloud.

The figure of thousand servers was thrown in the air by Bob Muglia; he also stated that somewhat smaller appliances were in the plans. Given that the container model requires a rather considerable amount of nodes in order to provide sufficient fault tolerance (remember: the container is probably replaced once a certain percentage of hardware requires replacement), I doubt we’ll see anything below 300 servers.

Why the Appliance?

The Appliance strikes an interesting balance. It provides the usually quoted benefits of private cloud (better control of data, less dependent on the Internet connectivity, faster data transfer inside the organization etc.). It also provides much of the public cloud benefits – most importantly computing without the need to setup or maintain the servers – the “serviceness”.

Scalability and elasticity don’t really apply to the appliance on a hardware level, but it does provide reasonable scalability inside the box. It remains to be seen if Microsoft will start supporting various more complex scenarios such as resource pooling between appliances and even perhaps the public cloud.

The appliances will be available both for hosters and end customers. Initial partners are HP, Fujitsu, Dell and eBay – the last of which is an actual customer. Since the big partners have their own datacenters around the globe, this also broadens Microsoft’s reach considerably: For example, organizations who have a legislative (or policy-based) need to keep their data in Finland could not have done so with Azure so far. However, a sufficiently big customer might buy a container of his own, or a smaller one might depend on Azure services provided by his local hosting company.

The pricing was not announced yet. This is an interesting point, because there is no precedent. Such appliances could be sold with a sizeable upfront cost, but they could also reasonably be rented. And yes, usage-based billing is an option too. If Microsoft decides to go with usage-based billing, it essentially takes a great step towards month-based licensing for on-premise software, a vision from long ago. At any rate, some monthly cost is definitely to be expected, given Microsoft’s commitment to providing the updates.

Sadly, no idea of the schedule so far.

July 13, 2010 · Jouni Heikniemi · 2 Comments
Tags: ,  · Posted in: Cloud, Windows IT

2 Responses

  1. Lebohang Bucibo - July 13, 2010

    Great article. Made a lot of things clear to me.

  2. Angel17 - February 28, 2023

    I enjoy reading this post. I find this so informative!

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