Microsoft Azure App Service, Cloud Services, or VMs?

Learn how to choose between Azure App Service, Azure Cloud Services, and Virtual Machines for hosting your app in the Azure Cloud

When I decided that I wanted to host a web application in the Azure cloud, the opportunity to explore the resources offered by a leading public cloud provider was exciting. How would Microsoft – with their deep experience and mature ecosystem – handle features like high availability, smart load balancing, and auto scaling?

It turns out that just choosing the right hosting service from Azure’s rich collection can be something of a challenge. My excitement quickly gave way to a little confusion and plenty of caution.

The right choice, of course, will depend on the unique needs of a project. We’ll explore some solutions from the MS Azure universe and try to highlight where they’re most likely to be useful.
Azure App Service Compute screenshot
Let’s focus on three services:

Azure App Service (which, until this past April, was called Azure Websites) is a managed platform. This means that Azure takes care of application deployment and management, while the developer only needs to concentrate on app development. Azure App Service supports applications defined by Azure as “Web Apps”, “Mobile Apps”, “API Apps”, and “Logic Apps”.

Azure Cloud Services is a platform that allows developers access to the underlying virtual machines and still manages the application container and deployment automatically. This offers a much more flexible solution than Azure App Service.

Virtual Machines give you full control over application management and deployment. For projects that may require substantial modifications to the technology stack in the future, or for people worried about being locked into a single vendor, the extra work required to launch and maintain Virtual Machines might be worth it.

Azure App Service

So, following the helpful Azure documentation, I successfully deployed my app using the App Service. Things went very smoothly… until I wanted to verify my server configurations and analyze some performance issues. It seems this isn’t possible, since App Service is a managed platform that handles deployment for you. There is no simple way to gain access to the app configuration files once it’s running.
In my case, this wasn’t ideal. I need remote access to the underlying web server, so that I can personally configure server tasks.

To fully understand how Azure App Service works, take a look at Cloud Academy’s Getting Started with Azure App Service course.

Azure Cloud Services

With that in mind, I turned my attention to Azure Cloud Services, which offers a slightly different balance of features. With Cloud Services, you can still enjoy a partially managed platform while, at the same time, maintaining some control over the underlying web servers. This documentation will guide you through deploying your web application using Cloud Services.

Learn more about Azure Cloud Services, in Cloud Academy’s Overview course of Azure Services.

Virtual Machines

What about Virtual Machines? I would say that, if you must have full access to configuration assets and you’re willing to accept the responsibility for managing your whole operation, this might be your best option.

Let’s spend a bit more time weighing these services against each other. As we said, if you are able to live without control over your webservers, then App Service might be for you. If it is, you’ll be able to enjoy some pretty impressive features, including:

  • Instant deployment.
  • Vertical scaling, without having to redeploy.
  • Support for multiple deployments (like staging and production).
  • Automatic OS upgrades for your infrastructure.
  • Integration capability with Git.
  • Integration capability with MySQL.

Azure App Service doesn’t completely lock you out, by the way. If you do sometimes need to run some background jobs along with your App Services deployment, Azure offers an integrated service called WebJobs. With WebJobs, users trigger custom programs or scripts on demand, continuously, or according to a set schedule. You can upload and run executable files built as cmd, bat, exe (.NET), ps1, sh, php, py, js, and jar with no trouble.

If Azure Cloud Services turns out to be a better fit, you’ll get many of the features of App Service, like support for multiple deployment, automatic OS upgrades, and seamless platform switching. But in addition, you’ll also get Remote Desktop (RDP) access to servers, custom MSI installations, the ability to define and execute start-up tasks, and to listen to Event Tracing for Windows (ETW) events.

And Virtual Machines? Here are some of the tasks that developers may still need to manually manage (Note that with some deployment solutions, these could also be automated):

  • Configuration of the application server/framework in the VM.
  • Integration with Azure services.
  • OS patch management.
  • Design and configure the application and infrastructure to handle fluctuating traffic.
  • Seamless platform switching (including the ability to move between 32 bit and 64 bit environments).
  • Security configuration.
  • Identify and apply monitoring strategy for applications.

To learn more on how to create, configure, and monitor VMs in Azure Resource Manager, take a look at Cloud Academy’s Azure Resource Manager Virtual Machines course.

Finally, here’s a partial list of some fantastic common features supported by all three services:

  • Access services like Service Bus, Storage, and SQL Database.
  • Host a web or web services tier of a multi-tier architecture.
  • Host a middle tier of a multi-tier architecture.
  • Support for ASP.NET, classic ASP, Node.js, PHP, and Python.
  • Scale out to multiple instances without having to redeploy.
  • Support for SSL.
  • Visual Studio integration.
  • Remote Debugging.
  • Network isolation with Azure Virtual Network.
  • Integrated Endpoint monitoring.

This diagram illustrates the level of control associated with all three of the Azure services we’ve been discussing:
Diagram showing the level of control associated to Virtual Machines, Cloud Services, and Web Apps While all of these services will host applications well, each has its own flavor. Naturally, you should base your choice on your individual business requirements.

This is a first step. There’s obviously much more to learn about these three solutions – and other Azure offerings – and I hope to continue to share my experiences as I learn and grow along with you. I appreciate your comments and encourage you to contribute when the spirit moves you.

Cloud Academy