Docker containers on shared windows runners lost internet connection

Using shared windows runners on gitlab.com, when running things in a docker container anything network related fails. It worked fine 4 days ago. Anything got changed in windows VMs?

Simplest way to repro is to run this as a script:
docker run mcr.microsoft.com/dotnet/sdk:6.0-windowsservercore-ltsc2019 curl https://api.nuget.org/v3/index.json

result:
curl: (6) Could not resolve host: api.nuget.org

Also works fine when run without container (well, dotnet restore etc work fine). Running the same container on my local workstation works fine.

Any ideas?

Looked at env variables, could not see anything relating to proxies etc.

Same issue here. I don’t think it’s related to Docker containers, since even outside a docker containe a simple ping doesn’t work. Was working fine a couple of days ago for me too, but it seems like outgoing connections are blocked in some way.

image1016×1177 129 KB

Same on my side, not longer able to resolve names using DNS. Four you it’s api.nuget.org, on my side it was github.com

But as far as I see it’s a problem with docker, when running it directly as command in the windows shared runner, everything is fine

My Dockerfile:

FROM mcr.microsoft.com/windows/servercore:ltsc2019

# Metadata indicating an image maintainer.
LABEL maintainer="xx@yy.zz"

RUN powershell Resolve-DnsName -Name github.com

Created a ticket for the problem:

The problem should be fixed now. For some reason, Docker containers stopped resolving DNS addresses until we entered in external DNS servers.

Yes, I can confirm that problem is fixed!