Enable the serial console on OpenShift Local

[kpouget]

To ease the troubleshooting

Console tty is either hvc0 or ttyS0, depending on the hypervisor

Summary by CodeRabbit

• New Features

  • Enabled serial console output on master nodes (hvc0 and ttyS0) to improve access to boot and runtime logs for troubleshooting.

• Chores

  • Added the master console configuration to manifest preparation so the new setting is applied to master nodes during deployment.

[coderabbitai]

Walkthrough

Adds a MachineConfig manifest enabling kernel console arguments for master nodes and updates snc.sh to copy that manifest into OpenShift manifests during preparation.

Changes

Cohort / File(s)	Summary
MachineConfig manifest (masters) 99-openshift-machineconfig-master-console.yaml	Adds a MachineConfig (apiVersion machineconfiguration.openshift.io/v1, kind MachineConfig) named 99-openshift-machineconfig-master-console with label machineconfiguration.openshift.io/role: master and spec.kernelArguments setting console=hvc0 and console=ttyS0.
SNC manifest preparation script snc.sh	Adds cp 99-openshift-machineconfig-master-console.yaml to include the new MachineConfig in the OpenShift manifests; removes a trailing blank line (cosmetic).

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant Dev as Developer
  participant SNC as snc.sh
  participant API as OpenShift API
  participant MCO as MachineConfig Operator
  participant Master as Master Nodes

  Dev->>SNC: run SNC workflow
  SNC->>SNC: prepare manifests (copy new MachineConfig)
  SNC->>API: apply manifests
  API->>MCO: create MachineConfig for masters
  MCO->>Master: reconcile kernelArguments (console=hvc0, console=ttyS0)
  Master-->>MCO: nodes updated

Loading

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

I nudge a YAML into place—hop!
Consoles wake on masters—pop!
The script copies, tidy and fleet,
hvc0 and ttyS0 meet.
Whiskers twitch—cluster hums discrete. 🐇✨

Pre-merge checks and finishing touches

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The title “Enable the serial console on OpenShift Local” concisely and accurately captures the primary change of enabling console output for local OpenShift instances, matching the addition of MachineConfig and script updates. It is clear, specific, and uses descriptive terms that reflect the PR’s objective. Team members scanning the history will immediately understand the main feature introduced by this merge.
Docstring Coverage	✅ Passed	No functions found in the changes. Docstring coverage check skipped.

✨ Finishing touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment

---

📜 Recent review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 7afd5b4 and d6617b0.

📒 Files selected for processing (2)

• 99-openshift-machineconfig-master-console.yaml (1 hunks)
• snc.sh (1 hunks)

🧰 Additional context used

🪛 YAMLlint (1.37.1)

99-openshift-machineconfig-master-console.yaml

[warning] 11-11: too many blank lines (1 > 0)

(empty-lines)

🔇 Additional comments (2)

99-openshift-machineconfig-master-console.yaml (1)

8-10: LGTM for the machine-config arguments.

Thanks for splitting the kernel arguments into separate entries; this matches what MCO expects.

snc.sh (1)

152-152: Fix the copy path to match the manifest’s location.

set -e makes the run abort because this command can’t find the file outside config/openshift/. Point the copy at the correct path so the serial-console MachineConfig actually gets staged.

-cp 99-openshift-machineconfig-master-console.yaml $INSTALL_DIR/openshift/
+cp config/openshift/99-openshift-machineconfig-master-console.yaml $INSTALL_DIR/openshift/

---

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[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please assign praveenkumar for approval. For more information see the Code Review Process.

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[coderabbitai]

Actionable comments posted: 2

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 39ffead and b8bbe81.

📒 Files selected for processing (2)

• 99-openshift-machineconfig-master-console.yaml (1 hunks)
• snc.sh (1 hunks)

[coderabbitai]

Actionable comments posted: 1

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between b8bbe81 and 7afd5b4.

📒 Files selected for processing (2)

• 99-openshift-machineconfig-master-console.yaml (1 hunks)
• snc.sh (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (1)

• snc.sh

🧰 Additional context used

🪛 YAMLlint (1.37.1)

99-openshift-machineconfig-master-console.yaml

[warning] 11-11: too many blank lines (1 > 0)

(empty-lines)

[openshift-ci]

@kpouget: The following test 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-snc	d6617b0	link	true	/test e2e-snc

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.

[kpouget]

[praveenkumar]

/cherry-pick release-4.20

[openshift-cherrypick-robot]

@praveenkumar: once the present PR merges, I will cherry-pick it on top of release-4.20 in a new PR and assign it to you.

In response to this:

/cherry-pick release-4.20

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.

[praveenkumar]

/cherry-pick master

[openshift-cherrypick-robot]

@praveenkumar: once the present PR merges, I will cherry-pick it on top of master in a new PR and assign it to you.

In response to this:

/cherry-pick master

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.

[openshift-cherrypick-robot]

@praveenkumar: new pull request created: #1164

In response to this:

/cherry-pick release-4.20

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.

[openshift-cherrypick-robot]

@praveenkumar: new pull request created: #1165

In response to this:

/cherry-pick master

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.