Expose ExternalIP of Node as annotation on headless service

[aaronhenshaw]

Use Case:
We need to have external-dns set our DNS to point to the ExternalIP of the node that the pod winds up on.

• Added an annotation "use-external-host-ip" for Services
• This will only work when "publish-host-ip" is set on the external-dns deployment

I believe this is kind of mentioned in #632

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[aaronhenshaw]

I signed it

[zzh8829]

This feature is very useful for people that don't use LoadBalancer from cloud providers.
Currently, the only other way to expose a service to ExternalIP is using NodePort.
However, NodePort is not a very ideal fit, since it doesn't work on ports < 3000.

I think supporting Headless ClusterIP + HostPort + ExternalIP is the way to go for this use case.
Hopefully we can get this PR released soon 🚀

[vsimon]

Should there be an err coming from getExternalIpFromAnnotations or should externalIp be checked instead? (as this is, this is checking the err coming from getTTLFromAnnotations)

[aaronhenshaw]

I removed the check, not sure it's necessary.

The only thing I could do would be if its not "true" but it exists I could throw an error. What do you think?

[aaronhenshaw]

@vsimon, @zzh8829 updated per feedback, let me know if there is anything else. Sorry it took so long, been so swamped recently.

[vsimon]

Thanks @aaronhenshaw, can't wait to check this out! The little script snippet in #632 has been chugging along without issue for months now 😃

[tommyknows]

Hi, any progress on this?
I think this feature would also be useful for scenarios where the loadbalancer IPs are in a NATed network.
For example, I have MetalLB provisioning IPs in 192.168.1.1xx, and am using port-forwarding on the router / firewall. I would like to expose the router's Public IP as the DNS endpoint, and not the private IP of the loadbalancer.
Would this PR allow this scenario too?

[aaronhenshaw]

Yeah I would love to get this merged if possible. Or if there is any other feedback I am happy to incorporate it. cc @vsimon @zzh8829

[vsimon]

I don't have any other feedback. I don't have approval privileges. The ball is on one of the approvers I guess.

[zzh8829]

I have been using my own docker image from this branch for a while, would be great if we can get this into the official image. @linki @Raffo do you guys have some time for code reviews?

[domingusj]

@zzh8829 any chance you could post the steps you used to create the modified container image? I'd also love to have this feature

[jeanlucmongrain]

I guess this project is falling in unmaintained status, if PR are ignored

[aaronhenshaw]

There is still regular activity here. It would be great to get an update or any info on getting this merged. I am happy to make changes, etc if that would help. @linki @Raffo

[zzh8829]

@domingusj i cloned this branch and then compiled dockerfile.
you can use my prebuild here at zihao/play:external-dns its 2 month old tho

[TheUltimateC0der]

I also did an image myself. Its based on the latest master. you can check the repo and image out here https://github.com/TheUltimateC0der/external-dns
https://hub.docker.com/r/theultimatecoder/external-dns

[domingusj]

Thank you @zzh8829 and @TheUltimateC0der. I'll do some testing this week. And hopefully your PR will get approved and released soon @aaronhenshaw! Thanks for the contribution!

[aaronhenshaw]

Hey any updates here. We would love to get this merged and move back to using the external-dns main releases!

Thanks!

[griffinchoe]

I went ahead and rebased this change onto the latest version of external-dns. We (along with many others waiting on this feature) would love to get this merged!

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/lifecycle stale

[mindw]

/remove-lifecycle stale

[seh]

#2115 merged, which might suffice as an alternative.

[k8s-ci-robot]

@aaronhenshaw: PR needs rebase.

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/lifecycle stale

[mindw]

/remove-lifecycle stale

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/lifecycle stale

[ThisIsQasim]

/remove-lifecycle stale

[k8s-triage-robot]

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/lifecycle stale

[mindw]

/remove-lifecycle stale

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/lifecycle stale

[ThisIsQasim]

/remove-lifecycle stale

[mloiseleur]

@aaronhenshaw Do you think you can rebase this PR ?

[mloiseleur]

Since author is not answering, I'm closing this PR.
Feel free to re-open it or open a new one if you need it.
/close

[k8s-ci-robot]

@mloiseleur: Closed this PR.

In response to this:

Since author is not answering, I'm closing this PR.
Feel free to re-open it or open a new one if you need it.
/close

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