Wednesday, April 28, 2010

Trouble in the Cloud

Our development team initially started using Microsoft Azure as our primary platform for hosting our external website. We signed up as a Community Technology Preview (CTP) member to receive the "Introductory Special," which gave us access to the content delivery network at no additional charge. Microsoft Azure guarantees that at least 99.95% of the time you will have connectivity and 99.9% of the time they will successfully process, add, update, read, and delete requests. Unfortunately, we have experienced at least 5 outages during a 3 month duration that we had NO control over. Due to these outages and many other issues we had while hosting with Microsoft Azure, our development team has decided to move our application from Microsoft Azure.

Let's talk about data backups. Well, there is not much to say, because you cannot back up your database or any of the content that is hosted with Microsoft Azure; however, you can take "snapshots" of a particular item in each of the containers that exist. In order to do this, we used a windows based client called Cloud Storage Studio by Cerebrata to manage our content: This product alleviated some of the qualms that we had with Microsoft Azure. Another alternative to data backups was simply creating a local copy of our SQL database and using SQL Compare by Redgate to synchronize our local SQL database with the SQL Azure tables in the cloud:

Pricing is another area to watch out for when using Microsoft Azure. Microsoft may lure you in with their "Introductory Special" offering free services and no monthly commitment. We experienced a high volume of outgoing and incoming requests early on and noticed how quickly the fees accumulated. In fact, our Azure costs nearly tripled by our third month. For more information about how the storage, data transfers, compute times, and transactions are measured, please read the Microsoft Azure pricing guide:

Uploading updates to the cloud has been a very painful process. Every time we uploaded an update to Microsoft Azure, it took anywhere from 15-25 minutes to process an 8-10MB package. This means 15-25 minutes of down time for our live application! That is not even the most frustrating part. Cache is not king when it comes to updating content on Microsoft Azure. Microsoft Azure utilizes dozens of servers across the world so you can have faster access to stored content. Unfortunately, if your application is cached across even a few of those servers it takes about 48-72 hours for the servers to update the cache. The caching option can be turned off; however, disabling this option may result in the loss of performance when accessing content. We experienced many issues with a simple change to a graphic not being reflected on the live application. We had to suspend or restart our live application, resulting in a loss of 15-20 minutes, just to see the change.

Overall, Microsoft Azure does have its advantages over a single server hosting solution. For instance, Microsoft Azure or any other cloud computing alternative might be the preferred platform when hosting a global application which processes data intensive transactions requiring bandwidth and computing power because it is supported globally.

In my opinion, Microsoft Azure is unstable and could be improved with the development of options such as remote access to the SQL Azure tables and a more efficient way to release application updates with less down time. After some thought and discussion over weaknesses we encountered while hosting with Microsoft Azure, our team has decided to move our application from Microsoft Azure onto a more stable, cost-effective single server hosting environment.

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