Skip to content

Modifying prefix_length for PSA to accomodate sufficient IPs for peering#5306

Merged
vikramvs-gg merged 1 commit into
GoogleCloudPlatform:release-candidatefrom
vikramvs-gg:psa-prefix-modify
Mar 3, 2026
Merged

Modifying prefix_length for PSA to accomodate sufficient IPs for peering#5306
vikramvs-gg merged 1 commit into
GoogleCloudPlatform:release-candidatefrom
vikramvs-gg:psa-prefix-modify

Conversation

@vikramvs-gg

Copy link
Copy Markdown
Contributor

Fix: Increase PSA IP range for gke-managed-lustre

The gke-managed-lustre blueprint allocates a /24 range for PSA (prefix_length: 24). The Managed Lustre service requires a certain number of IPs within the producer network that is peered with VPC. A /24 looks to be insufficient for the internal needs of the services.

This change increases the allocated range size by modifying the prefix_length in the private-service-access module from 24 to 22. This increases the number of IP addresses reserved for the service producer, making it more resilient to IP exhaustion within the tenant project.

Testing: The integration test associated with gke-managed-lustre blueprint is now successful with the change which was failing due to PSA IPs exhausted for service earlier.

  • Fork your PR branch from the Toolkit "develop" branch (not main)
  • Test all changes with pre-commit in a local branch #
  • Confirm that "make tests" passes all tests
  • Add or modify unit tests to cover code changes
  • Ensure that unit test coverage remains above 80%
  • Update all applicable documentation
  • Follow Cluster Toolkit Contribution guidelines #

@vikramvs-gg vikramvs-gg requested a review from samskillman as a code owner March 3, 2026 07:03
@vikramvs-gg vikramvs-gg added the release-bugfix Added to release notes under the "Bug fixes" heading. label Mar 3, 2026
@vikramvs-gg vikramvs-gg requested a review from a team as a code owner March 3, 2026 07:03
@gemini-code-assist

Copy link
Copy Markdown
Contributor

Summary of Changes

Hello, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves an IP exhaustion issue within the GKE-managed Lustre service by expanding the allocated IP range for Private Service Access (PSA). The prefix_length has been adjusted from /24 to /22, significantly increasing the number of available IP addresses. This change ensures that the service producer has sufficient IPs for its internal needs, enhancing the overall resilience and stability of the system by preventing future IP address depletion within tenant projects.

Highlights

  • Increased Private Service Access (PSA) IP Range: The prefix_length for Private Service Access (PSA) in the gke-managed-lustre blueprint has been increased from /24 to /22 to provide a larger pool of IP addresses and prevent exhaustion.
  • Updated Example Configurations: Various GKE blueprint examples (gke-a3-ultragpu, gke-a4, gke-a4x, gke-tpu-7x, gke-tpu-v6e) have been updated to reflect the new recommended prefix_length of /22 for PSA.
  • Documentation Update: The README.md for the managed-lustre module has been updated to show the adjusted prefix_length in its example configuration.
Changelog
  • examples/gke-a3-ultragpu/gke-a3-ultragpu.yaml
    • Updated the commented prefix_length for private service access from 24 to 22.
  • examples/gke-a4/gke-a4.yaml
    • Updated the commented prefix_length for private service access from 24 to 22.
  • examples/gke-a4x/gke-a4x.yaml
    • Updated the commented prefix_length for private service access from 24 to 22.
  • examples/gke-managed-lustre.yaml
    • Increased the prefix_length for private service access from 24 to 22.
  • examples/gke-tpu-7x/gke-tpu-7x-advanced.yaml
    • Updated the commented prefix_length for private service access from 24 to 22.
  • examples/gke-tpu-v6e/gke-tpu-v6e-advanced.yaml
    • Updated the commented prefix_length for private service access from 24 to 22.
  • modules/file-system/managed-lustre/README.md
    • Updated the example prefix_length in the documentation from 24 to 22.
Activity
  • No specific activity (comments, reviews, etc.) has been recorded for this pull request yet.
Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature Command Description
Code Review /gemini review Performs a code review for the current pull request in its current state.
Pull Request Summary /gemini summary Provides a summary of the current pull request in its current state.
Comment @gemini-code-assist Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help /gemini help Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

  1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution.

@gemini-code-assist gemini-code-assist Bot left a comment

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Code Review

This pull request correctly increases the prefix_length for Private Service Access from 24 to 22 to provide a larger IP range for gke-managed-lustre, which is necessary for the service to function correctly. The change is consistently applied across the main gke-managed-lustre blueprint, several other examples where Lustre is an option, and the module's documentation. My review includes suggestions to add explanatory comments to these changes, which align with the repository's style guide and do not contradict any established rules. This will improve the long-term maintainability and clarity of the blueprints by explaining why this specific value is used.

Comment thread examples/gke-a3-ultragpu/gke-a3-ultragpu.yaml
Comment thread examples/gke-a4/gke-a4.yaml
Comment thread examples/gke-a4x/gke-a4x.yaml
Comment thread examples/gke-managed-lustre.yaml
Comment thread examples/gke-tpu-7x/gke-tpu-7x-advanced.yaml
Comment thread examples/gke-tpu-v6e/gke-tpu-v6e-advanced.yaml
Comment thread modules/file-system/managed-lustre/README.md

@SwarnaBharathiMantena SwarnaBharathiMantena left a comment

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

LGTM

@vikramvs-gg vikramvs-gg merged commit 8f655b4 into GoogleCloudPlatform:release-candidate Mar 3, 2026
13 of 75 checks passed
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

release-bugfix Added to release notes under the "Bug fixes" heading.

Projects

None yet

Development

Successfully merging this pull request may close these issues.

2 participants