[external-lb]: kubelet.conf server address and kube-proxy api-server address fix

[ugur99]

What type of PR is this?
/kind bug

What this PR does / why we need it:
When trying to configure external lb address for already provisioned clusters; it does not set correct external lb fqdn address for worker nodes, instead of it sets first controlplane's ip address.

The problem is that kubeadm does not update the kubeadm-config configmap in kube-system namespace; it only creates that config in kubeadm init phase, even though it creates new ClusterConfiguration on controlplane node in /etc/kubernetes/kubeadm-config.yaml path. Since worker nodes fetch configMap on the cluster when the kubeadm join ... command is run, it was fetching old clusterConfig in already provisioned clusters.

To fix this problem, we added a new task to update kubelet.conf in worker nodes. We also noticed that kube_proxy was not getting the right address for external lb is the case; and we added logic to update kube_proxy config as well.

EDIT: Just a quick edit to fix misunderstanding on my side; it looks like kubeadm fetches the cluster-info configmap in the kube-public namespace to create a new kubelet.conf. But it is the best to handle this on the kubespray side instead of relying on the configmap on the cluster.

Special notes for your reviewer:
For testing purposes, a new cluster was set up and tested.

Does this PR introduce a user-facing change?:

Fix external-lb in kubelet.conf server address and kube-proxy api-server address 

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: ugur99 / name: Ugur Can Ozturk (c0c7787)
• ✅ login: pehlicd / name: Furkan Pehlivan (2409876, 3b29bba)

[k8s-ci-robot]

Hi @ugur99. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[yankay]

/ok-to-test

[ugur99]

Hi @yankay! Is there anything else you would like us to do regarding this PR? I think the failing required pipeline has nothing to do with our commits, right?

[yankay]

Hi @yankay! Is there anything else you would like us to do regarding this PR? I think the failing required pipeline has nothing to do with our commits, right?

HI @ugur99

The CI had been broken in 1st Oct, and it has been fixed :-)
Would you please repush it, and triger the CI to pass it again .

Thanks you :-)

[pehlicd]

Hi @yankay,

I merged master to our branch and triggered the CI again. It seems like there is no failed pipeline. Please let us know if you need further actions.

Thanks 🙂

[yankay]

Thanks @pehlicd

/lgtm

[floryut]

@ugur99 Thank you for the PR 👍

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: floryut, ugur99

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