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Unable to bind to http://localhost:5000 on the IPv6 loopback interface: 'Cannot assign requested address'

See original GitHub issue

Describe the bug

My ASP.NET Core 5 application works fine locally in Mac/Windows when debugging through VS Code, Rider or VS. But when when trying to spin up a container from the image, it will always give the following warning and the application would not respond to any request.

warn: Microsoft.AspNetCore.Server.Kestrel[0]
      Unable to bind to http://localhost:5000 on the IPv6 loopback interface: 'Cannot assign requested address'.

To Reproduce

Create any ASP.NET Core 5 application and add the following line in Startup.cs.ConfigureServices(IServiceCollection services) method. services.AddSingleton(sp => Configuration); Someone else asked the question before as well: https://stackoverflow.com/q/65836031/1565402

Exceptions (if any)

none

Further technical details

.NET SDK (reflecting any global.json): Version: 5.0.102 Commit: 71365b4d42

Runtime Environment: OS Name: Mac OS X OS Version: 11.0 OS Platform: Darwin RID: osx.11.0-x64 Base Path: /usr/local/share/dotnet/sdk/5.0.102/

Host (useful for support): Version: 5.0.2 Commit: cb5f173b96

VS 2019, VS Code, Rider

Issue Analytics

State:
Created 3 years ago
Comments:8 (7 by maintainers)

Top GitHub Comments

1reaction

halter73commented, Mar 2, 2021

Thanks @lluchmk!

1reaction

Tratchercommented, Feb 5, 2021

Binding to localhost binds to two separate addresses, 127.0.0.1 (IPv4) and ::1 (IPv6). Some environments like containers will not support one, but still successfully start on the other. That’s why this is a warning and not an error.

@halter73 should this be downgraded to Info, and only produce an error if both fail?

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