Unable to access .Net App deployed in Heroku docker - docker

Question

I deployed .NET app on Heroku docker
deploying went good no error
but when I tried to open the app I'm getting error
tried a few things like created VAR named PORT and gave value 5000 doesn't workout
2023-01-22T12:30:50.674761+00:00 heroku[web.1]: Starting process with command `dotnet ./Muapp.dll --urls\=http://\*:5000`
2023-01-22T12:30:51.685276+00:00 app[web.1]: Welcome to Muapp!
2023-01-22T12:30:51.685567+00:00 app[web.1]:
2023-01-22T12:30:51.685571+00:00 app[web.1]:
2023-01-22T12:30:51.909353+00:00 app[web.1]: warn: Microsoft.AspNetCore.DataProtection.Repositories.FileSystemXmlRepository[60]
2023-01-22T12:30:51.909375+00:00 app[web.1]: Storing keys in a directory '/app/.aspnet/DataProtection-Keys' that may not be persisted outside of the container. Protected data will be unavailable when container is destroyed.
2023-01-22T12:30:51.928587+00:00 app[web.1]: warn: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[35]
2023-01-22T12:30:51.928590+00:00 app[web.1]: No XML encryptor configured. Key {f5035bc0-d6dd-402b-92f8-51341dd3511a} may be persisted to storage in unencrypted form.
2023-01-22T12:30:54.638199+00:00 app[web.1]: info: Microsoft.Hosting.Lifetime[14]
2023-01-22T12:30:54.638211+00:00 app[web.1]: Now listening on: http://[::]:5000
2023-01-22T12:30:54.642119+00:00 app[web.1]: info: Microsoft.Hosting.Lifetime[0]
2023-01-22T12:30:54.642121+00:00 app[web.1]: Application started. Press Ctrl+C to shut down.
2023-01-22T12:30:54.642714+00:00 app[web.1]: info: Microsoft.Hosting.Lifetime[0]
2023-01-22T12:30:54.642715+00:00 app[web.1]: Hosting environment: Production
2023-01-22T12:30:54.642715+00:00 app[web.1]: info: Microsoft.Hosting.Lifetime[0]
2023-01-22T12:30:54.642716+00:00 app[web.1]: Content root path: /app
2023-01-22T12:31:50.857290+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch
2023-01-22T12:31:50.888117+00:00 heroku[web.1]: Stopping process with SIGKILL
2023-01-22T12:31:51.047126+00:00 heroku[web.1]: Process exited with status 137
2023-01-22T12:31:51.113768+00:00 heroku[web.1]: State changed from starting to crashed
2023-01-22T13:53:20.502985+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=oby.herokuapp.com request_id=6e089f4e-52e2-4c32-b28f-efc7999777ac fwd="104.28.255.112" dyno= connect= service= status=503 bytes= protocol=https
2023-01-22T13:53:22.376963+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=oby.herokuapp.com request_id=824189c7-7244-4070-bccb-7af1b4584e78 fwd="104.28.255.112" dyno= connect= service= status=503 bytes= protocol=https
2023-01-22T13:53:27.109966+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=oby.herokuapp.com request_id=eb7e2b1b-37d4-471c-9514-43da912b827d fwd="104.28.255.112" dyno= connect= service= status=503 bytes= protocol=http
2023-01-22T13:53:28.779659+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=oby.herokuapp.com request_id=6c5c88ed-ac9a-4e70-b422-d0bf294baeb4 fwd="104.28.255.112" dyno= connect= service= status=503 bytes= protocol=http

Answer 1

Heroku assigns you a port that it wants you to listen on. That port is passed to you in an environment variable called PORT. So you can't decide that you want to listen on port 5000 as that will very likely not be the port Heroku assigns you.
When Heroku discovers that you haven't bound to the assigned port, it kills your container.
To bind to the correct port, change your startup command to
dotnet ./Muapp.dll --urls=http://*:${PORT}