SocketException when running MCP server on Azure App Service

[AndreaC-MSFT]

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• Protocol Specification
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Your Question

I've created a test SSE MCP server based on ModelContextProtocol.AspNetCore. I can run it fine locally and can connect to it from a client.
However, when I run it on Azure App Service, I get System.Net.Sockets.SocketException (10013): An attempt was made to access a socket in a way forbidden by its access permissions.
I've checked that the port configuration is fine (it's all mapped on port 80).
Am I missing something?

[AndreaC-MSFT]

On troubleshooting I realized that this was caused by the fact that I deployed the app as self-contained. Switching to portable resolved the issue.