The service is unavailable multi container app

Question

Hello.

I have had an testing crud app (https://nuxtcrud.azurewebsites.net/) working under multi container docker-compose file with Basic Azure plan, and it was fine. But when I migrated to Standard plan the app doesn't work.

The result when visit the app is "The service is unavailable" and about register container the result is "Container logs could not be loaded: Containerlog resource of type text not found".

Thanks in advance.

Answer 1

Thanks for asking question! Looking internally Below is the findings:

There were total 33- 503 error, as service unavailable, as described due to Servers unavailable ( we ran out of workers).

Current Sku for (https://nuxtcrud.azurewebsites.net/) is Linux Free

You may want to know that App Service scale unit is a collection of servers that host and run your applications. A typical scale unit can have more than 1,000 servers. The clustering of servers enables economy of scale and reuse of shared infrastructure. The main functionality of scale unit is to host and run customer applications. Applications run on Windows servers and are referred to as Web Workers or Workers for short. The majority of servers in a given scale unit are Workers.

Workers are the backbone of the App Service scale unit. They run your applications.

With App Service, you can choose how you want to run your application. You can select running your application on shared or dedicated servers. You do so by selecting an App Service Plan. An App Service Plan defines a set of capabilities, features and server allocations.

A Shared Worker hosts applications from multiple different customers where Dedicated Workers are guaranteed to run one or more applications of a single customer. There are several dedicated server types and sizes from which you can choose. The larger the server size, the more CPU and memory resources are available for allocated applications. The App Service Plan defines the amount of pre-allocated servers for your application.

Example here.

To know more about Front Ends, Workers and to understand internals of Azure App service Architecture, please read below article
Azure - Inside the Azure App Service Architecture.

Check this link: https://learn.microsoft.com/en-us/azure/app-service/troubleshoot-http-502-http-503#troubleshooting-steps-to-solve-502-bad-gateway-and-503-service-unavailable-errors

Let us know if issue remains.