CORS-4208: set default KUBELET_NODE_IPS for dualstack nodes

[tthvo]

- What I did

This updates the master and worker kubelet service templates to set the defaults KUBELET_NODE_IPS.

• DualStack: default to 0.0.0.0
• DualStackIPv6Primary: default to ::

This set the --node-ip (i.e. to 0.0.0.0 or ::) kubelet argument when enabling dualstack support on cloud providers, where node ip is not beforehand.

- Why I did

When investigating failures related to dual-stack support on AWS, I noticed kubelet ran without the --node-ip=<any-id> argument. As a result, CNI never came online, while complaining that node was missing the InternalIP address. For example, results from a failed attempt returned the following errors:

Component	Failed log
ovnkube-controller container	F0903 17:41:46.149835 5622 ovnkube.go:138] failed to run ovnkube: [failed to start network controller: failed to start default network controller - while waiting for any node to have zone: "i-041d879bce674db11.ec2.internal", error: context canceled, failed to start node network controller: failed to init default node network controller: i-041d879bce674db11.ec2.internal doesn't have an address with type InternalIP or ExternalIP]
kubelet	Error syncing pod, skipping" err="network is not ready: container runtime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:Network plugin returns error: no CNI configuration file in /etc/kubernetes/cni/net.d/. Has your network provider started?"
kube-rbac-proxy-crio container	failed to initialize certificate reloader: error loading certificates: error loading certificate: open /var/lib/kubelet/pki/kubelet-server-current.pem: no such file or directory

After some research and trial, I determined that the kubelet --node-ip is necessary. It must be set to 0.0.0.0 or :: (ipv6-primary) in case of dualstack. After ensuring the argument is set, node was assigned InternalIP address and CNI progressed successfully.

- How to verify it

Tested with openshift/installer#9930. Alternatively, the installer can lay down a environment file to set the env var (for example, openshift/installer@9fa264d), but I think it seems quite hacky 😞

- Description for the changelog

Update the master and worker kubelet service templates to set the defaults KUBELET_NODE_IPS (i.e. 0.0.0.0 for Dualstack and :: for DualStackIPv6Primary)

[openshift-ci-robot]

@tthvo: This pull request references CORS-4208 which is a valid jira issue.

In response to this:

- What I did

This updates the master and worker kubelet service templates to set the defaults KUBELET_NODE_IPS.

• DualStack: default to 0.0.0.0
• DualStackIPv6Primary: default to ::

This set the --node-ip (i.e. to 0.0.0.0 or ::) kubelet argument when enabling dualstack support on cloud providers, where node ip is not beforehand.

- How to verify it

Tested with openshift/installer#9930. Alternatively, the installer can lay down a environment file to set the env var, but I think it is quite hacky.

- Description for the changelog

Update the master and worker kubelet service templates to set the defaults KUBELET_NODE_IPS (i.e. 0.0.0.0 for Dualstack and :: for DualStackIPv6Primary)

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[tthvo]

/cc @sadasu @patrickdillon

[openshift-ci-robot]

@tthvo: This pull request references CORS-4208 which is a valid jira issue.

In response to this:

- What I did

This updates the master and worker kubelet service templates to set the defaults KUBELET_NODE_IPS.

• DualStack: default to 0.0.0.0
• DualStackIPv6Primary: default to ::

This set the --node-ip (i.e. to 0.0.0.0 or ::) kubelet argument when enabling dualstack support on cloud providers, where node ip is not beforehand.

- Why I did

When investigating failures related to dual-stack support on AWS, I noticed kubelet ran without the --node-ip=<any-id> argument. As a result, CNI never came online, while complaining that node was missing the InternalIP address. For example, results from a failed attempt returned the following errors:

Component	Failed log
ovnkube-controller container	F0903 17:41:46.149835 5622 ovnkube.go:138] failed to run ovnkube: [failed to start network controller: failed to start default network controller - while waiting for any node to have zone: "i-041d879bce674db11.ec2.internal", error: context canceled, failed to start node network controller: failed to init default node network controller: i-041d879bce674db11.ec2.internal doesn't have an address with type InternalIP or ExternalIP]
kubelet	Error syncing pod, skipping" err="network is not ready: container runtime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:Network plugin returns error: no CNI configuration file in /etc/kubernetes/cni/net.d/. Has your network provider started?"
kube-rbac-proxy-crio container	failed to initialize certificate reloader: error loading certificates: error loading certificate: open /var/lib/kubelet/pki/kubelet-server-current.pem: no such file or directory

After some research and trial, I determined that the kubelet --node-ip is necessary. It must be set to 0.0.0.0 or :: (ipv6-primary) in case of dualstack. After ensuring the argument is set, node was assigned InternalIP address and CNI progressed successfully.

- How to verify it

Tested with openshift/installer#9930. Alternatively, the installer can lay down a environment file to set the env var (for example, openshift/installer@9fa264d), but I think it seems quite hacky 😞

- Description for the changelog

Update the master and worker kubelet service templates to set the defaults KUBELET_NODE_IPS (i.e. 0.0.0.0 for Dualstack and :: for DualStackIPv6Primary)

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[tthvo]

Not sure if I am doing the right thing 😓 , but with openshift/installer#9930, this change worked as expected. This was only tested with AWS.

Pending confirmations for other platforms 👀 PTAL 🙏

[tthvo]

/retest

[sadasu]

/cc @cybertron and @mkowalski Could you PTAL ? This is required for adding DualStack support for AWS and Azure.

[cybertron]

While it feels a little weird to set KUBELET_NODE_IPS to a single value, since all we're really doing is telling it whether to prefer v4 or v6 I think this should be okay. Also worth noting that for the on-prem platforms we override these values anyway so it shouldn't affect us. Just to be sure though:

/test e2e-metal-ipi-ovn-dualstack
/test e2e-metal-ipi-ovn-ipv6

[sadasu]

Are the changes to the on-prem files done to maintain consistency? Test prove that the changes are fine. I am leaning towards not making any changes to on-prem files even if harmless.

[tthvo]

Are the changes to the on-prem files done to maintain consistency? Test prove that the changes are fine. I am leaning towards not making any changes to on-prem files even if harmless.

Right, it was done for consistency. Thus, I removed the changes for on-prem unit files now as suggested 👍

[tthvo]

Thanks everyone for the reviews and insights! I addressed the comments just now. PTAL again 🙏

[openshift-ci]

@tthvo: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-openstack	a113f54	link	false	/test e2e-openstack
ci/prow/bootstrap-unit	07ae9ad	link	false	/test bootstrap-unit
ci/prow/okd-scos-e2e-aws-ovn	07ae9ad	link	false	/test okd-scos-e2e-aws-ovn

Full PR test history. Your PR dashboard.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.