Friday, September 17, 2010

Stupid Cloud Tricks #1: Hosting a Web Site Completely from Windows Azure Storage

Can you host a web site in Windows Azure without using Windows Azure Compute? Sure you can: you can ‘host’ an entire web site in Windows Azure Storage, 100% of it, if the web site is static. I myself am currently running several web sites using this approach. Whether this is a good idea is a separate discussion. Welcome to “Stupid Cloud Tricks” #1. Articles in this series will share interesting things you can do with the Windows Azure cloud that may be non-obvious and whose value may range from “stupid” to “insightful” depending on the context in which you use them.

If you host a web site in Windows Azure the standard way, you’re making use of Compute Services to host a web role that runs on a server farm of VM instances. It’s not uncommon in this scenario to also make use of Windows Azure blob storage to hold your web site assets such as images or videos. The reason you’re able to do this is that blob storage containers can be marked public or private, and public blobs are accessible as Internet URLs. You can thus have HTML <IMG> tags or Silverlight <Image> tags in your application that reference images in blob storage by specifying their public URLs.

Let’s imagine we put all of the files making up a web site in blob storage, not just media files. The fact that Windows Azure Storage is able to serve up blob content means there is inherent web serving in Windows Azure Storage. And this in turn means you can put your entire web site there—if it’s of the right kind: static or generated web sites that serve up content but don’t require server-side logic. You can however make use of browser-side logic using JavaScript or Ajax or Silverlight.

How does ‘hosting’ a static web site out of Windows Azure Storage compare to hosting it through Windows Azure Compute?
  • With the standard Windows Azure Compute approach, a single VM of the smallest variety @$0.12/hr will cost you about $88/month--and you need at least 2 servers if you want the 3 9's SLA. In addition you’ll pay storage fees for the media files you keep in Windows Azure storage as well as bandwidth fees.
  • If you put your entire site in Windows Azure storage, you avoid the Compute Services charge altogether but you will now have more storage to pay for. As a reminder, storage charges include a charge for the amount of storage @$0.15/GB/month as well as a transaction fee of $0.01 per 10,000 transactions. Bandwidth charges also apply but should be the same in either scenario.
So which costs more? It depends on the size of your web site files. In the Compute Services scenario the biggest chunk of your bill is likely the hosting charges which are a fixed cost. In the storage-hosted scenario you’re converting this aspect of your bill to a charge for storage which is not fixed: it’s based on how much storage you are using. It’s thus possible for your 'Storage-hosted’ web site charges to be higher or lower than the Compute-hosted approach depending on the size of the site. In most cases the storage scenario is going to be less than the Compute Services scenario.

As noted, this is only useful for a limited set of scenarios. It’s not clear what this technique might cost you in terms of SLA or Denial of Service protection for example. Still, it’s interesting to consider the possibilities given that Windows Azure Storage is inherently a web server. The reverse is also true, Windows Azure Compute inherently comes with storage--but that’s another article.


Anonymous said...

Does it really have to be static? Why not use Silverlight or AJAX as your dynamic UI layer? Forget about ASP.NET, if it can call back to the server ..

Check this out ..

David Pallmann said...

It's static as far as what the 'web server' fetches--you can't have any server-side logic with this approach such as ASP.NET code-behind. I believe I did mention you can implement logic via JavaScript, Ajax, or Siverlight.

Re your post I certainly agree there's a tier shift going on. When we use technologies like Silverilght all the tiers move closer to the user's machine.

Glenn Ferrie said...

Great post. We've been playing around with this concept as well. Primarily, for hosting app prototypes built in Expression Blend (Silverlight).


andy said...

I always enjoy learning how other people employ Microsoft Azure. I am wondering if you can check out my very own tool CloudBerry Explorer that helps manage Azure Blob Storage . It is a freeware.