Add ipv6 load balancer tests

[petrutlucian94]

This PR adds ipv6-only and ipv6-dualstack load balancer tests. Note that the ipv6-only test is currently skipped due to a known cilium limitation:

• Cilium fails to start with IPv4 disabled cilium/cilium#15082
• Support tunneling over IPv6 cilium/cilium#17240

[bschimke95]

Great work @petrutlucian94
Added a couple of comments. Please also move the year change to a separate PR. Thanks!

[petrutlucian94]

Please also move the year change to a separate PR. Thanks!

I had to run make format to avoid lint job failures but it bumped the headers. I'll open a separate PR.

[bschimke95]

looks like the dualstack test is not yet working.

[petrutlucian94]

looks like the dualstack test is not yet working.

I'll rebase the PR to get the metallb logs, fwiw it passed locally.

[petrutlucian94]

Strange, the test passes locally and the metallb logs seem fine. The lb ip gets assigned properly, however it's not accessible, but only in case of a dualstack environments.

"status": {
                "loadBalancer": {
                    "ingress": [
                        {
                            "ip": "10.10.61.4",
                            "ipMode": "VIP"
                        }
                    ]
                }
            }

I think I'll have to use this to take a look inside the GH runner: https://github.com/mxschmitt/action-tmate

[petrutlucian94]

The dualstack test uses a separate bridge, so the Docker workaround had to be applied there as well. Thanks @berkayoz for the suggestion!

[petrutlucian94]

Interesting, test_strict_interfaces is now failing:

____________________________ test_strict_interfaces ____________________________
Traceback (most recent call last):
  File "/home/ubuntu/actions-runner/_work/k8s-snap/k8s-snap/tests/integration/tests/test_strict_interfaces.py", line 33, in test_strict_interfaces
    util.setup_k8s_snap(cp, tmp_path, channel, connect_interfaces=False)
  File "/home/ubuntu/actions-runner/_work/k8s-snap/k8s-snap/tests/integration/tests/test_util/util.py", line 202, in setup_k8s_snap
    instance.exec(cmd)
  File "/home/ubuntu/actions-runner/_work/k8s-snap/k8s-snap/tests/integration/tests/test_util/harness/lxd.py", line 227, in exec
    return run(
  File "/home/ubuntu/actions-runner/_work/k8s-snap/k8s-snap/tests/integration/tests/test_util/util.py", line 44, in run
    return subprocess.run(command, **kwargs)
  File "/home/ubuntu/actions-runner/_work/_tool/Python/3.10.16/x64/lib/python3.10/subprocess.py", line 526, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['lxc', 'shell', 'k8s-integration-a370fb-53', '--', 'bash', '-c', 'snap install --classic k8s --channel latest/edge/strict']' returned non-zero exit status 1.

I see a permission error:

error: cannot perform the following tasks:
- Run configure hook of "k8s" snap if present (run hook "configure": 
-----
Warning: meta.orb is none, skipping reconcile actions
mkdir: cannot create directory ‘/etc/systemd/system/snap.k8s.containerd.service.d’: Permission denied
-----)

We should probably disable this test since the strict branch is known as broken and the strict jobs are disabled as well.

[bschimke95]

It is fine to disable the test for now but we should still be aware of such issues. I created a card to investigate this in the future.
We likely broke this test when we changed the containerd path.

[bschimke95]

LGTM