There are new options for using the cloud for some workloads -- options that did not exist, or were prohibitively expensive, in the Windows Server 2003 era but that are now realistic for many organizations. Let's take a look.
Public cloud options to choose from
For enterprises, there are three main offerings in the public cloud:
Microsoft Azure. Microsoft's cloud service was built to run Windows and related services and is currently engaged in a price war with next player on this list, meaning you could really get a lot of bang for your buck.
Amazon Web Services. The grandfather of all cloud services, Amazon offers much in the way of enterprise services, can run Windows, offers networking solutions to cross your premises boundaries, and is worthy of consideration.
Google Cloud. This nascent player in the marketplace has really been focused on the software as a service demographic and is not yet a key player in the enterprise realm. Watch this space, regardless, as the cloud giant grows.
Public cloud pros
There are several pros to moving off of Windows Server 2003 and into the cloud. Here are just
You get instant deployment for a number of workloads without having to spin up bare metal on premises. Forget having to select hardware, size it appropriately, go through the requisition process, unbox the hardware, rack it, power it, deploy it, lay down an operating system on it and patch it. That's a process that from the "Hey, we need another machine" moment to installing your workload on the metal can take from weeks to months. With a public cloud, you put in your credit card and in a matter of minutes you can have a well-oiled virtual machine, or in some cases a platform as a service instance like Azure Web Sites, spun up and ready to serve requests.
You get insurance if your needs change or you need to scale up or down on short notice. One of the most common technical demonstrations you will see Microsoft in particular perform with respect to its Microsoft Azure service is the ability to scale capacity with just a couple of clicks of the mouse -- for Black Friday sales, for one time event launches, or for other periods of intense demand wherein your normal hardware capacity would be quickly exhausted.
Using a public cloud for these workloads, which in general are customer facing and involve web page serving and database calls, frees up a lot of capital expense in that you no longer have to purchase and size your hardware investment to handle your peaks. You can simply right-size and deploy hardware based on your nominal load, and use a service like Azure to handle the biggest days or period of demand.
Public cloud cons
There are, of course, some downsides in moving to the public cloud. Here are some considerations.
Your costs are unpredictable. While your costs in the first year or two of using cloud to either replace or augment your existing server infrastructure will certainly be less than acquiring the hardware in the first place, as times wears on, you will eventually spend more in recurring expenses than you would to fulfill the workload on your own hardware under your control. You are at the mercy of the public cloud provider in terms of what rates they charge, what notice they have to give you regarding rate changes or even whether they continue offering a particular product. In the event they stop offering a certain product, it's unclear how you will be compensated financially for the attendant transition costs. Put simply, you will pay less at first, but you may pay more over time and you give up direct control over your costs entirely. This may be a tradeoff worth making, however.
You lose control over your data. In some industries and in some jurisdictions, this is a bigger deal than in others, but when you move any sort of workload to a hosted environment where the machines live outside your locus of control, you lose control of your data. Should the SEC, FBI, UK agencies, or the European Space Agency request a subpoena or equivalent and want the hard drive of the machine that is storing and or serving your data at the time, they will get it, and there is very little your hosting company can do to stop it. If data security is of the utmost importance to you, then moving to the public cloud is a bad idea.
You lose direct control over compatibility. If you take advantage of some infrastructure as a service offerings from your cloud provider, then in some cases you may lose control over when you are upgraded from one version of an operating system or application to another, what patch level you are running at, and in general you give up the capability of assessing compatibility between all of the moving parts that make up your IT offering. If you still want to run Windows Server 2008 gold in Azure, for example, it's as simple as saying you definitely cannot. You are put on the train of constant upgrades. The good news? These are handled for you. The bad news? These are handled for you.
In the end, many of the questions you'll need to answer when deciding on a cloud option come down to cost versus control.