Web App vs Cloud App in Terms of Cost

Question

I am writing a Node.js app to run a REST API. Because the API will eventually power a mobile app, I made the mistake of creating a mobile service in Azure, which wasn't the right choice for me as it couldn't support the existing Node code I wrote. Now I'm deciding whether to deploy it as a web app or a cloud service. I don't need control of the VM, and I don't need to dictate the specifics of the environment, so I was leaning towards making it as a web app. But then, I decided to compare the pricing of the two options. To get a core to myself on a basic web service, it would be about $56 per month, and it wouldn't even include auto scaling, but my own core through the cloud services would be about $15 per month, including auto scaling. Now I'm thinking that it seems like a better idea to deploy it as a cloud service, where I can get three cores and autoscaling for the same price.

Are there major differences between the two affecting my project? E.g. would I have to manually implement load balancing on a cloud service, and how would scaling on a web app compare to scaling on a cloud service? Am I misunderstanding the pricing model?

Answer 1

Hi,

Azure App Service is the best choice for most web apps. Deployment and management are integrated into the platform, sites can scale quickly to handle high traffic loads, and the built-in load balancing and traffic manager provide high availability.

If you need more control over the web server environment, such as the ability to remote into your server or configure server startup tasks, Azure Cloud Services is typically the best option.

If you have an existing application that would require substantial modifications to run in Azure App Service or Azure Cloud Services, you could choose Azure Virtual Machines in order to simplify migrating to the cloud. However, correctly configuring, securing, and maintaining VMs requires much more time and IT expertise compared to Azure App Service and Cloud Services. If you are considering Azure Virtual Machines, make sure you take into account the ongoing maintenance effort required to patch, update, and manage your VM environment and so the prices are comparatively less as that of Azure web app.

The load balancing services can be accessed by specifying input endpoints on your services either via the Microsoft Azure Portal or via the service model of your application. Once a hosted service with one or more input endpoints is deployed in Microsoft Azure, it automatically configures the load balancing services offered by Microsoft Azure platform. To get the benefit of resiliency / redundancy of your services, you need to have at least two virtual machines serving the same endpoint.

Regards,

Shirisha Paderu

Answer 2

So it sounds like the differences in my case are very minor. I won't be able to manage it as easily and I will have to manually define the endpoints if I go with a cloud service. Do you have any thoughts on the cost difference? App Service is clearly better suited for my actual project, but it seems like a cloud service could also work since for me.

Answer 3

Reubend, what options do you exactly compare? By the cost $15 per month I assume you are looking at A0, is that correct?

The web app service starts with an equivalent of A1, so twice as memory (1.7 GB against 0.75 GB) and a dedicated core (against a shared core) for your app in comparison to A0 instance.

Thanks,
Petr

Answer 4

Hey Petr, 

I'm comparing Cloud Service A0 ($15) to App Service B1 ($56). If I understand correctly, those are the cheapest prices for a single exclusive core. It sounds from your post like the A0 is actually shared... could you elaborate on that? 

Answer 5

If you navigate to subscription limits info page ( https://azure.microsoft.com/en-us/documentation/articles/azure-subscription-service-limits/ ), there is a note for "cores per subscription" limit:

      Extra Small instances count as one core towards the core limit despite using a partial core.

Basically the machine is not as powerful as regular B1 or A1.

Hope this helps.

Thanks,
Petr

Answer 6

Ah, ok. Do they they have the same limit on number of minutes per day as the normal shared instances?

Answer 7

What do you mean by a normal shared instance? If you mean a "shared web app", that's a different thing. I believe the extra small (A0) instance does not really have a limit of minutes per day, it juts runs slower than other sizes.

Answer 8

Ok, that's what I was wondering. Thank you!