Debug App Service 503 / 500 error

raj p lartians 101 Reputation points
2020-12-18T17:02:58.923+00:00

I am getting 500 timeout / 503 service unavailable errors on my Azure App service. I am deploying code to our QA environment and the same code to our staging environment. The QA and staging environment both run on S2:1 service plans.

For some reason both hang and I get 4 minute response times for about 4 hours. The staging environment seems to recover at this point but the QA does not. I am trying to debug the issue by getting the memory dump and call stack profiler trace from diagnostic tools, but neither seem helpful. I have tried adding pdb to the Devops deployment to view what is going on in the profiler but when I try to load module symbols is does not find anything and I see that total CPU is 99% for [External Code]. Can someone help me get this setup properly?

Azure App Service
Azure App Service
Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
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  1. Ryan Hill 26,771 Reputation points Microsoft Employee
    2020-12-18T21:00:54.04+00:00

    Hi @raj p lartians ,

    I'm not sure if you have seen https://azure.github.io/AppService/2018/06/06/App-Service-Diagnostics-Profiling-an-ASP.NET-Web-App-on-Azure-App-Service.html but it contains some insights on how to understand the report from the profiler trace. Including running the included *.diagsession through Perfview. Perfview will allow you to load your symbols to gain better insights on the trace file. Another option you could look at using Application Insights to profile your application.

    Feel free to post any screen shots or attachments of your trace down below for an extra set of eyes.

    Regards,
    Ryan