It is very familiar. “XXX works fine locally but does not work at all in production”.
I am going to take assumption that the environment variable, ASPNETCORE_ENVIRONMENT, will be used to determine whether the application is running in Development mode or Production mode. Setting it as “Development.
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Next move to Azure App services.
Within Azure Portal, add ASPNETCORE_ENVIRONMENT to the Application settings. Instead of “Development”, we will use “Production” here. Navigate to the App Service for the application, then navigate to Configuration:
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Turn on App Service Logs to Filesystem in App Service
Within Azure Portal, navigate to App Service logs, Turn on Web server logging. This creates the folder path “D:\home\LogFiles\http\RawLogs” and starts writing server log files there.
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A few benefits of us writing Serilog rolling files in the same location:
1-One single spot to access logs
2-When Application Logging (Filesystem) is turned on, you can view the Serilog logs in the Log Stream under App Service Monitoring section as well! Awesome!
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Test and view the log files
Assuming your app service URL is https://YourWebAppName.azurewebsites.net, while being logged into Azure Portal, visit https://YourWebAppName.SCM.azurewebsites.net which is the Kudu site. You should be able to locate the log files by going to Debug console/CMD and navigate to “D:\home\LogFiles\http\RawLogs”.
Another spot to diagnose the problem is to look here;
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And on the next page, look here;
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It is easy to develop and test locally but when you deploy the application to Azure App Service, a few extra steps are required so that logs are properly populated and accessible within the Azure App Service.
Resources
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