Accessing my gRPC services hosted on Azure as Linux Web App doesn't work since 2024-07-19 anymore!

Question

Since 2024-07-17 our application hosting gRPC Services isn't accessible on Azure anymore and I can't figure out any configuration issues from my side.

• The App is hosted as App Service (Linux) with Service Plan B2
• 'HTTP Version' is set 2.0
• 'HTTP 2.0 Proxy' is set to 'gRPC only'
• 'SSH' is on
• 'HTTPS Only' is on
• Min. inbount TLS is set to '1.2'
• Environment variable 'HTTP20_ONLY_PORT' is set to '8585' according to the Microsoft Learn documentation

Accessing the app using a HTTPS GET returns the 'Communication with gRPC endpoints must be made through a gRPC client.' correctly. But connecting with a gRPC client isn't possible. Always Error 502 (Service unavailable)

I've tried without success:

• 'HTTP 2.0 Proxy' changed from 'gRPC Only' to 'on'
• 'HTTP 2.0 Proxy' changed to 'off' and accessing the App Service using the port-number 8585 in the URL

In the Log stream i see when HTTP 1.1 GET occurs, but nothing about HTTP 2.0 connection tries.

Nothing seems to work. Please help!

Answer 1

We had the exact same problem, and we solved it by upgrading the tier, restarting the app service, and then downgrading it to the tier we had before and also restarting.

Answer 2

The same problem, since 17/7/2024 it seems that after microsoft maintenance action it breakdown, if anyone got the help from tech support please share the solution because technical support works very slowly and we still wait for the answer

Answer 3

Ok subscription plan was the problem. After we upgraded to higher plan/subscription our service started working again, cheaper subscription doesn't include the HTTP 2.0 Proxy

Answer 4

I have exactly the same problem with grpc service since 31/08/2024 using P0v3 plain. How can I resolve this?

Answer 5

Microsoft seem to have fixed the issue, we have made no changes to the service and now it works again.