IPv6 support added

[danehans]

Feature Description

• One-line feature description (can be used as a release note): Adds support for IPv6, allowing full Kubernetes capabilities using IPv6 networking instead of IPv4 networking.
• Primary contact (assignee): @danehans
• Responsible SIGs: sig-network
• Kubernetes Enhancement Proposal PR: Graduate IPv6 support to beta #1139
• Reviewer(s) - (for LGTM) recommend having 2+ reviewers (at least one from code-area OWNERS file) agreed to review. Reviewers from multiple companies preferred: @thockin @bowei @luxas
• Approver (likely from SIG/area to which feature belongs): @thockin
• Feature target (which target equals to which milestone):
  • Alpha release target 1.9

[luxas]

@danehans Thanks for filing this feature issue!
cc @idvoretskyi FYI

[danehans]

xref ipv6 issue: kubernetes/kubernetes#1443

[zacharysarah]

@danehans 👋 Please indicate in the 1.9 feature tracking board
whether this feature needs documentation. If yes, please open a PR and add a link to the tracking spreadsheet. Thanks in advance!

[danehans]

@zacharysarah I only have comment access to the 1.9 feature tracking board, so I added comments for the IPv6 docs requirement.

cc: @mmueen

[danehans]

@zacharysarah does the 1.9-release changelog need to be manually updated to reference any of the IPv6 PRs or kubernetes/kubernetes#1443?

[zacharysarah]

@danehans When you say changelog, do you mean the release notes?

/cc @Bradamant3 for release notes visibility

[danehans]

Yes, I am trying to understand if anything needs to be added to the 1.9 release notes, and if so, what process to follow. Thank you.

[luxas]

This should have a release note

[zacharysarah]

/cc @Bradamant3 @nickchase Release note visibility! ☝️

[xiangpengzhao]

@danehans 1.9 release note draft is here:
https://docs.google.com/document/d/1veHHyDH9VoNTwP6yy9u2Q7Jj1hnBJGVPv3NPHInImgU/edit

You can follow the guidance at the top of the doc.

xref: https://groups.google.com/forum/#!topic/kubernetes-sig-release/x6ySPIJkMN4 by @enisoc

[danehans]

@xiangpengzhao I have updated the 1.9 release notes with the ipv6 support details. Please let me know if add'l ipv6 content is required for the 1.9 release notes.

[xiangpengzhao]

@danehans I think the details you added are good enough 👍 . But personally I'd like to see the associated PRs (if existing) for the bullets.

• IPv6 alpha support has been added. Notable IPv6 support details include:
  • Support for IPv6-only Kubernetes cluster deployments. This feature does not provide dual-stack support.
  • Support for IPv6 Kubernetes control and data planes.
  • Support for Kubernetes IPv6 cluster deployments using kubeadm.
  • Support for the iptables kube-proxy backend using ip6tables.
  • Relies on CNI 0.6.0 binaries for IPv6 pod networking.
  • Although other CNI plugins support IPv6, only the CNI bridge and local-ipam plugins have been tested for the alpha release.
  • Adds IPv6 support for kube-dns using SRV records.
  • Caveats
    • HostPorts are not supported.
    • An IPv6 network mask for pod or cluster cidr network must be /66 or longer. For example: 2001:db1::/66, 2001:dead:beef::/76, 2001:cafe::/118 are supported. 2001:db1::/64 is not supported

[xiangpengzhao]

@danehans I took another look at the release note and found that you put the ipv6 details into the section Before Upgrading. I don't think we should put them there.

[danehans]

@xiangpengzhao The only concern I have is that several PRs were used for the different bullets.

[danehans]

@xiangpengzhao I have moved the IPv6 content for the 1.9 release notes. Please let me know if you have any further concerns.

[xiangpengzhao]

@danehans That LGTM :)

[valentin2105]

I use Kubernetes on IPv6-only (v1.8.x) for a while now,
and the biggest problem to solve, I think, Is to detect if IPv6 is enabled to stop to use ClusterIPs (10.32.x.x) on clusters.

[xiangpengzhao]

@valentin2105 can you please open an issue in k/k to track this if you think it is an issue should be solved?
https://github.com/kubernetes/kubernetes/issues

[justaugustus]

@danehans
Any plans for this in 1.11?

If so, can you please ensure the feature is up-to-date with the appropriate:

• Description
• Milestone
• Assignee(s)
• Labels:
  • stage/{alpha,beta,stable}
  • sig/*
  • kind/feature

cc @idvoretskyi

[danehans]

@leblancd is leading the IPv6 charge. I will let him comment.

[leblancd]

@justaugustus - This should probably be broken into 2 separate issues:
IPv6-Only support: Release 1.9, Alpha
Dual-Stack Support: Release 1.11, Alpha
I think this issue (#508) is sufficient for IPv6-Only support, and a new Issue will be needed for dual-stack.

[leblancd]

/kind feature

[unixfox]

Which IPv6 feature landed into Kubernetes 1.18? Is it dual stack or IPv6 only graduated to beta?
I'm confused because nothing changed in the docs.

[aojea]

Which IPv6 feature landed into Kubernetes 1.18? Is it dual stack or IPv6 only graduated to beta?
I'm confused because nothing changed in the docs.

This issue tracks ipv6 only, graduated to beta in 1.18

Dual stack is alpha and is tracked in other issue/KEP

[palnabarun]

/milestone clear

(removing this enhancement issue from the v1.18 milestone as the milestone is complete)

[kikisdeliveryservice]

Hi @aojea @danehans ,

1.19 Enhancements shadow here. I wanted to check in and see if you think this Enhancement will be graduating in 1.19?

In order to have this part of the release:

The KEP PR must be merged in an implementable state
The KEP must have test plans
The KEP must have graduation criteria.

The current release schedule is:

Monday, April 13: Week 1 - Release cycle begins
Tuesday, May 19: Week 6 - Enhancements Freeze
Thursday, June 25: Week 11 - Code Freeze
Thursday, July 9: Week 14 - Docs must be completed and reviewed
Tuesday, August 4: Week 17 - Kubernetes v1.19.0 released

Please let me know and I'll add it to the 1.19 tracking sheet (http://bit.ly/k8s-1-19-enhancements). Once coding begins please list all relevant k/k PRs in this issue so they can be tracked properly. 👍

Thanks!

[aojea]

Thanks @kikisdeliveryservice , but I think we should focus now in dual stack.
No change here during this release

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

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/lifecycle stale

[unixfox]

/remove-lifecycle stale

[kikisdeliveryservice]

Hi @aojea @danehans

Enhancements Lead here. Any plans to graduate this in 1.20?

Thanks,
Kirsten

[aojea]

Hi @aojea @danehans

Enhancements Lead here. Any plans to graduate this in 1.20?

nope 😄

[kikisdeliveryservice]

thanks for the update!

[sep76]

Is there any documentation on how to verify ipv6 only operations ? google only lead me to ipv4 or ipv6 dualstack.

[aojea]

Is there any documentation on how to verify ipv6 only operations ? google only lead me to ipv4 or ipv6 dualstack.

what do you mean by "verify"?

The installation for IPv6 only is the same as in IPv4, just you need to use IPv6 addresses and subnets in your configuration, no additional changes needed.
https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/#initializing-your-control-plane-node

[chrisnew]

Can confirm. I run 1.17.x in ipv6-only mode. Just follow the IPv4 guide and use IPv6 addresses. That’s basically it.

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[unixfox]

/remove-lifecycle stale

[telmich]

Question: does this ticket also include a working IPv6 kube-router or not? Because as far as I know, kube-router does not work in IPv6 only networks.

[aojea]

Question: does this ticket also include a working IPv6 kube-router or not? Because as far as I know, kube-router does not work in IPv6 only networks.

what do you mean by kube-router?

[telmich]

Question: does this ticket also include a working IPv6 kube-router or not? Because as far as I know, kube-router does not work in IPv6 only networks.

what do you mean by kube-router?

I am referring to cloudnativelabs/kube-router#988

[aojea]

that project is independent of kubernetes --- kubernetes supports IPv6, another thing is the ecosystem and all the related projects that works or use kubernetes :)

[aojea]

Let's centralise everything here #563
for people finding this issue: IPV6 only works, but since kubernetes dual-stack is beta in 1.21, IPv6 will graduate with dual-stack to GA
/close

[k8s-ci-robot]

@aojea: Closing this issue.

In response to this:

Let's centralise everything here #563
for people finding this issue: IPV6 only works, but since kubernetes dual-stack is beta in 1.21, IPv6 will graduate with dual-stack to GA
/close

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