Change:
// create pod which using hostport on the specified node according to the nodeSelector func createHostPortPodOnNode(f *framework.Framework, podName, ns, hostIP string, port int32, protocol v1.Protocol, nodeSelector map[string]string, expectScheduled bool) { <ins> hostIP = framework.TranslateIPv4ToIPv6(hostIP) </ins> createPausePod(f, pausePodConfig{ Name: podName, Ports: []v1.ContainerPort{

Discussion:
<!-- Please only use this template for submitting reports about failing tests in Kubernetes CI jobs --Which jobs are failing: https://k8s-(IPv6),%20master%20(dev) Which test(s) are failing: [sig-scheduling] SchedulerPredicates [Serial] validates that there is no conflict between pods with same hostPort but different hostIP and protocol [Conformance] Since when has it been failing: Testgrid link: https://k8s-(IPv6),%20master%20(dev) Reason for failure: The tests checks for 0.0.0.0 that is IPv4 only Anything else we need to know: Probably I should check with SIG-Testing how can we add an ipv6 job and update the KEP accordingly EDIT Probably I should check with SIG-Testing how can we add an ipv6 job as part of the k/k presubmits, and update the KEP accordingly
/assign /cc
/sig scheduling

<!-- Please only use this template for submitting enhancement requests --What would you like to be : Introduce a mechanism that allows specifying the IP protocol version used in the e2e testing. Why is this needed: This is a followup on , my understanding is that in order to discriminate between IPv4 or IPv6 we have to use the test labels and this adds complexity to the testing automation and doesn't allow to send this information to the context of the tests. Having a mechanism to specify the IP protocol will simplify the testing for IPv4 and IPv6 and will allow reusing most of the code.
/sig testing /cc /assign Does this make sense? If affirmative, what should be the best way to add this functionality? Checking the code I think that or can provide this, don't know if checking some of the cluster config parameters, ...
the testing-commons group (sig-testing) maintains the framework, but ideally the decision on how to proceed in terms of adding ipv6 detection should come from sig-network. possibly having this as agenda for a sig-network meeting is a good start, then discussing it in a testing-commons meeting. /sig network the linked issue is a big one, so i don't have all the context here. but IMO existing tests should just work for ipv6 without the requirement for a new "IPV6" tag in test names. dual-stack or protocol specific tests should have their descriptions contain the details properly (i.e. what is this test doing) we might want to add an utility function under: (there is a PR to move it BTW ) then such an utility might be useful only to tests that need to detect the protocol. one of the goals is to refactor the code in testcontext / framework, so adding this logic there is less preferred.
/area e2e-test-framework
I think that we can add an option to test_context to specify the cluster IP family the same way that exists one for the cloud provider this is simpler because when setting up the CI jobs you will know beforehand what IP family you want to test, it also will allow reusing all the e2e code for IPv6 and Dual Stack (cc: and by default will be IPv4, so it´s backward compatible.
Being able to override and specify exactly what you want the test to beleive about your cluster is nice, but ideally it should generally work without specifying more flags.

Surely we can detect this?
I was thinking during some time about this, detecting the IP family is very simple having IPv4 or IPv6 only clusters, but with the introduction of dual stack I´m afraid about the supportability and reliability of the autodetecting mechanisms in the long term. If you see the dual stack PRs there are still a lot of unknowns about the cluster behavior. My point is, let´s have something first stable that works and is simple, and once dual stack is implemented, we can replace the flag with a function in the framework . I guess that migrating from a flag variable to a function is straight forward, is just replacing by , what do you think?
in is as part of the context. do you mean adding as a function which will auto-detecting the ip family. less flags for the framework binary is preferred.
once we have this I will open a new issue to start cleaning up and , we no longer need to discriminate based on tags