chore: Remove binding of ports to IPv4 only

[daviian]

What does this PR do?

Removes the HostIP from the Port Binding so that it does not restrict itself to IPv4.

Why is it important?

Not needed anymore.

Related issues

• Closes [Enhancement]: Resolve port bindings according to IPv4 and IPv6 #825
• Closes [Bug]: ryuk container are not shutdown #1360

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[HofmeisterAn]

Thanks

[BrunoJuchli]

Could this possibly have caused the problem described here to re-occur?
Since updating to TestContainers 4.2.0 we experience randomly failing tests.
From the error symptoms it looks like we're connecting to the wrong port of the container.
To give some context:

We run a fake SMTP Server in a docker container. The system-under-test connects to the SMTP port to send emails.
The test connects to the HTTP Port to retrieve all emails that have been sent.

The ports are configured using ContainerBuilder.WithPortBinding(int port, assignRandomHostPort: true)

We've not modified this code in the last few months; it used to work reliably.
Now we get SMTP responses on our HTTP Requests.

Of course, this being a timing/concurrency issue, it's entirely likely that the root cause has existed in the beginning, and only the execution timing has shifted recently.

[HofmeisterAn]

@BrunoJuchli Which container runtime do you use?

[BrunoJuchli]

@HofmeisterAn
Thank you for the super quick reply 🥇
Unfortunately I'm not too knowledgeable in this area, is it by chance what I get from the logs here?

[testcontainers.org 00:00:00.17] Connected to Docker:
Host: unix:///var/run/docker.sock
Server Version: 26.1.3
Kernel Version: 6.8.0-1021-azure
API Version: 1.45
Operating System: Ubuntu 24.04.1 LTS

We're running this on GitHub Action - Ubuntu-latest. If the info above doesn't make it obvious to you on first sight what container runtime is used, I'm happy to dig deeper.
In that case I guess I will have to look into the runner-image and find out whether containerd, wasmtime, gvisor, kata containers,... is used, and which version thereof, correct?

[HofmeisterAn]

@HofmeisterAn Thank you for the super quick reply 🥇 Unfortunately I'm not too knowledgeable in this area, is it by chance what I get from the logs here?

[testcontainers.org 00:00:00.17] Connected to Docker:
Host: unix:///var/run/docker.sock
Server Version: 26.1.3
Kernel Version: 6.8.0-1021-azure
API Version: 1.45
Operating System: Ubuntu 24.04.1 LTS

We're running this on GitHub Action - Ubuntu-latest. If the info above doesn't make it obvious to you on first sight what container runtime is used, I'm happy to dig deeper. In that case I guess I will have to look into the runner-image and find out whether containerd, wasmtime, gvisor, kata containers,... is used, and which version thereof, correct?

I assume you're encountering a different issue. I think the issue you're referring to is related to environments running Docker Desktop. I haven't noticed any flakiness in our CI pipeline (we're using GH-hosted runners too, though we use Ubuntu 22.04).

Have you been using 24.04 for a while? I believe there were some issues with the runners in general, if I'm not mistaken.

[BrunoJuchli]

I assume you're encountering a different issue. I think the issue you're referring to is related to environments running Docker Desktop. I haven't noticed any flakiness in our CI pipeline (we're using GH-hosted runners too, though we use Ubuntu 22.04).

Have you been using 24.04 for a while? I believe there were some issues with the runners in general, if I'm not mistaken.

@HofmeisterAn
Thanks for the tip! We've not been using Ubuntu 24 for long.

I've executed some test runs with Ubuntu 24 and Ubuntu 22. Since our tests are quite long-running, the sample size isn't large - and the conclusion not a 100% reliable, but:

• Ubuntu 24: 2 out of 5 tests runs fail
• Ubuntu 22: 0 out of 6 test runs fail.

From previous runs I see that close to half of the test runs on Ubuntu 24 in recent days failed. So having 6 test runs on Ubuntu 22 pass looks like a reliable enough indicator to me.
= we're switching to Ubuntu 22, for now.

[HofmeisterAn]

For reference, we have encountered some issues with the VM images in the past (anyone that depends on Docker) due to incompatible kernel versions. I do not know the exact details, but you can find more information about those issues here:

• MSSQL containers crashing after recent update actions/runner-images#10649
• fix: Bump MSSQL image version, remove Azure SQL Edge and Papercut module #1265

It might be a good idea to start running our tests against version 24.04 as well, to see if there are any issues we can address or information we need to provide to the upstream: GitHub Actions Runner Images.