OCPBUGS-77094: [release-4.20] nodeallocator: fix subnet leak when hybrid overlay is enabled

[aswinsuryan]

Clean backport of 2990

When the hybrid overlay feature is enabled (specifically when hybrid overlay cluster subnets are configured), the HandleDeleteNode function would return early after releasing the hybrid overlay subnet. This caused the regular cluster subnets allocated to the node to never be released, leading to a subnet leak that eventually exhausts the cluster CIDR pool.

This commit fixes the issue by removing the early return, ensuring that both the hybrid overlay subnets and the standard node subnets are properly released upon node deletion.

A new test case TestNodeAllocator_HandleDeleteNode is added to verify that both types of subnets are correctly released.

📑 Description

Fixes #

Additional Information for reviewers

✅ Checks

• My code requires changes to the documentation
• if so, I have updated the documentation as required
• My code requires tests
• if so, I have added and/or updated the tests as required
• All the tests have passed in the CI

How to verify it

[openshift-ci-robot]

@aswinsuryan: This pull request references Jira Issue OCPBUGS-77094, which is invalid:

• release note text must be set and not match the template OR release note type must be set to "Release Note Not Required". For more information you can reference the OpenShift Bug Process.
• expected dependent Jira Issue OCPBUGS-77086 to be in one of the following states: VERIFIED, RELEASE PENDING, CLOSED (ERRATA), CLOSED (CURRENT RELEASE), CLOSED (DONE), CLOSED (DONE-ERRATA), but it is POST instead

Comment /jira refresh to re-evaluate validity if changes to the Jira bug are made, or edit the title of this pull request to link to a different bug.

The bug has been updated to refer to the pull request using the external bug tracker.

Details

In response to this:

When the hybrid overlay feature is enabled (specifically when hybrid overlay cluster subnets are configured), the HandleDeleteNode function would return early after releasing the hybrid overlay subnet. This caused the regular cluster subnets allocated to the node to never be released, leading to a subnet leak that eventually exhausts the cluster CIDR pool.

This commit fixes the issue by removing the early return, ensuring that both the hybrid overlay subnets and the standard node subnets are properly released upon node deletion.

A new test case TestNodeAllocator_HandleDeleteNode is added to verify that both types of subnets are correctly released.

📑 Description

Fixes #

Additional Information for reviewers

✅ Checks

• My code requires changes to the documentation
• if so, I have updated the documentation as required
• My code requires tests
• if so, I have added and/or updated the tests as required
• All the tests have passed in the CI

How to verify it

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

This pull-request has been approved by: aswinsuryan
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[openshift-ci]

Hi @aswinsuryan. Thanks for your PR.

I'm waiting for a openshift 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.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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Details

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[aswinsuryan]

closing since combined backport PR is raised

[openshift-ci-robot]

@aswinsuryan: This pull request references Jira Issue OCPBUGS-77094. The bug has been updated to no longer refer to the pull request using the external bug tracker.

Details

In response to this:

Clean backport of 2990

When the hybrid overlay feature is enabled (specifically when hybrid overlay cluster subnets are configured), the HandleDeleteNode function would return early after releasing the hybrid overlay subnet. This caused the regular cluster subnets allocated to the node to never be released, leading to a subnet leak that eventually exhausts the cluster CIDR pool.

This commit fixes the issue by removing the early return, ensuring that both the hybrid overlay subnets and the standard node subnets are properly released upon node deletion.

A new test case TestNodeAllocator_HandleDeleteNode is added to verify that both types of subnets are correctly released.

📑 Description

Fixes #

Additional Information for reviewers

✅ Checks

• My code requires changes to the documentation
• if so, I have updated the documentation as required
• My code requires tests
• if so, I have added and/or updated the tests as required
• All the tests have passed in the CI

How to verify it

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.