Auto discovery default certificate and certificate list

[abeowlu]

Issue

#4090

Description

AWS ELB API ignores the default certificate when certificate list is provided in TLS negotiation.
The auto discovered default certificate is needed for TLS negotiation. Adding the default certificate discovered to the extre certificate list

brief logic change:

• add default certificate to extraCert list as AWS ELBs ignores default certificate in certain SNI TLS negotiation scenario
• TODO discussion: accept user specified default certificate - skipping as certificate-arn implements similar functionality, and that logic shortcircuits auto-discovery execution

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: abeowlu / name: Abraham Olu (1741147)

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @abeowlu. Thanks for your PR.

I'm waiting for a github.com 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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[zac-nixon]

/ok-to-test

Seems good to me. We'll include this in our first release of the new year.

[k8s-triage-robot]

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/lifecycle stale

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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

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[abeowlu]

/retest

[abeowlu]

/retest

[abeowlu]

@zac-nixon , looks like flakiness in the test? failing on a security group deletion dependency

{"level":"error","ts":"2026-03-18T23:16:01Z","msg":"Reconciler error","controller":"service","namespace":"service-ip-e2e-a8bf95","name":"ip-e2e","reconcileID":"17cd11b0-9ae3-4031-a998-f666485e08bb","error":"failed to delete securityGroup: timed out waiting for the condition"}

[k8s-ci-robot]

@abeowlu: 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
pull-aws-load-balancer-controller-e2e-test	1741147	link	true	/test pull-aws-load-balancer-controller-e2e-test

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all PRs.

This bot triages PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the PR is closed

You can:

• Mark this PR as fresh with /remove-lifecycle rotten
• Close this PR with /close
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle rotten

[k8s-ci-robot]

PR needs rebase.

Details

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