NetApp Volumes: mount large-capacity volumes via Cloud DNS by okrause · Pull Request #6186 · GoogleCloudPlatform/cluster-toolkit

okrause · 2026-08-20T14:24:55Z

Large-capacity volumes and FlexCache expose multiple NFS endpoint IPs. Add volume dns_config and private-zone support so clients, including Slurm, mount by FQDN and use every endpoint. Update EDA and Slurm examples plus docs.

Goal is to have a larger populations of clients spread their clients evenly (statistically) over all endpoint IPs to even out load on storage backend.

gemini-code-assist · 2026-08-20T14:28:00Z

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 introduces support for mounting large-capacity NetApp volumes and FlexCache caches via Cloud DNS. By configuring a private DNS zone, clients can now mount storage using an FQDN that resolves to multiple NFS endpoint IPs in a round-robin fashion. This change addresses the limitation where clients previously only utilized a single IP address, significantly improving load distribution and performance for compute-heavy workloads like Slurm.

Highlights

DNS-based Volume Mounting: Introduced a new dns_config parameter to the netapp-volume module, allowing volumes to be mounted via FQDN using Cloud DNS round-robin for improved performance.
Enhanced DNS Module: Updated the dns-managed-zone module to support private visibility and multiple VPC networks, enabling secure internal DNS resolution for storage endpoints.
New Example Blueprint: Added netapp-volumes-slurm.yaml, a new blueprint demonstrating a Slurm cluster configuration that leverages DNS-backed volume mounting.
Documentation Updates: Updated EDA blueprints and general network storage documentation to reflect the new DNS-based mounting patterns for large-capacity volumes and FlexCache.

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gemini-code-assist

Code Review

This pull request introduces private Cloud DNS integration for Google Cloud NetApp Volumes and FlexCache, enabling clients to mount large-capacity volumes and caches using a single FQDN that resolves to multiple NFS endpoint IPs via DNS round-robin. It updates the EDA blueprints, adds a new Slurm example blueprint (netapp-volumes-slurm.yaml), and updates the relevant modules and documentation. Feedback on the changes suggests removing the redundant google_project_service resource for dns.googleapis.com inside the netapp-volume module to prevent potential permission conflicts and avoid requiring elevated Service Usage permissions during deployment.

aslam-quad · 2026-08-21T08:51:46Z

Please NOTE : We recently upgraded our repository's Go version to 1.26 (#6173). We strongly recommend rebasing your open branches onto the latest develop branch to avoid or resolve any PR test failures.

Thank you!

okrause · 2026-08-21T09:17:32Z

/gemini review

gemini-code-assist

Code Review

This pull request introduces support for mounting large-capacity Google Cloud NetApp Volumes and FlexCache caches using private Cloud DNS round-robin FQDNs, which distributes Slurm clients across multiple NFS endpoints. It updates the netapp-volume and dns-managed-zone modules, adds a new netapp-volumes-slurm example blueprint, and updates the EDA blueprints and documentation. Feedback suggests stripping the trailing dot from the generated FQDN in dns.tf using trimsuffix to prevent potential NFS client mount failures.

okrause · 2026-08-21T09:40:45Z

/gemini review

gemini-code-assist

Code Review

This pull request introduces support for mounting large-capacity Google Cloud NetApp Volumes and FlexCache caches using private Cloud DNS round-robin FQDNs, which distributes client mounts across multiple NFS endpoints in Slurm clusters. It updates the netapp-volume and dns-managed-zone modules, adds a new netapp-volumes-slurm.yaml example, and updates the EDA blueprints and documentation. Feedback on the changes highlights a potential race condition in dns.tf where downstream modules might attempt to mount the volume before the DNS record is fully active; establishing an implicit dependency on the DNS record set resource is recommended to ensure proper provisioning order.

okrause · 2026-08-24T08:17:41Z

/gemini review

gemini-code-assist

Code Review

This pull request introduces support for mounting large-capacity Google Cloud NetApp Volumes and FlexCache caches using private Cloud DNS round-robin A records, allowing Slurm clients to distribute mounts across all available NFS endpoint IPs via FQDNs. The changes update the netapp-volume and dns-managed-zone modules, add a new netapp-volumes-slurm example blueprint, and update existing EDA blueprints and documentation. Feedback on the changes suggests restricting the unix_permissions for the /home filesystem in the new blueprint from 0777 to 0755 to prevent security risks associated with world-writable home directories.

okrause · 2026-08-24T08:36:42Z

@agrawalkhushi18 This is ready to review.

okrause · 2026-09-01T15:57:07Z

I accidentally pushed other code on this branch. I reverted it back to good commit. My apologies.

github-actions · 2026-09-08T00:43:05Z

this PR has been inactive for 6 days and has no unresolved comments. @vikramvs-gg, please review.

vikramvs-gg · 2026-09-08T06:16:25Z

/gcbrun

vikramvs-gg

LGTM

vikramvs-gg · 2026-09-09T04:58:06Z

/gcbrun

github-actions · 2026-09-12T00:40:18Z

this PR has been inactive for 2 days and has no unresolved comments. @vikramvs-gg, please review.

agrawalkhushi18 · 2026-09-12T13:26:03Z

/gcbrun

okrause · 2026-09-14T07:48:29Z

@vikramvs-gg @agrawalkhushi18 Thank you for your approval. Very appreciated. Can you tell me why the pipeline it not moving forward? We have two approvals.

agrawalkhushi18 · 2026-09-14T08:11:41Z

/gcbrun

Large-capacity volumes and FlexCache expose multiple NFS endpoint IPs. Add volume dns_config and private-zone support so clients, including Slurm, mount by FQDN and use every endpoint. Update EDA and Slurm examples plus docs.

okrause · 2026-09-14T10:01:57Z

Thank you for triggering the run. Turns our region and zone where missing from the new examples/netapp-volumes-slurm.yaml blueprint. I added them. Should work now.

agrawalkhushi18 · 2026-09-14T10:33:47Z

Thank you for triggering the run. Turns our region and zone where missing from the new examples/netapp-volumes-slurm.yaml blueprint. I added them. Should work now.

Thanks @okrause . But why are we hardcoding the region and zone values in the sample blueprint?

okrause · 2026-09-14T11:04:18Z

Thank you for triggering the run. Turns our region and zone where missing from the new examples/netapp-volumes-slurm.yaml blueprint. I added them. Should work now.

Thanks @okrause . But why are we hardcoding the region and zone values in the sample blueprint?

@agrawalkhushi18 One of the PR workflows (IIRC it is PR-validation) validates all the example blueprints. There seem to be two types of tests. The smaller ones are ran in tools/validate_configs/validate_configs.sh and need hard-coded values. There are many other blueprints in examples/ which take that approach. Since I did not pass region and zone, this happend:

Step #1 - "make-tests": 2026-09-14T08:53:41Z: Error: deployment variable "region" was not set
Step #1 - "make-tests": 27:   region:     ## Set GCP Region Here ##
Step #1 - "make-tests":       ^
Step #1 - "make-tests": Error: deployment variable "zone" was not set
Step #1 - "make-tests": 28:   zone:       ## Set GCP Zone Here ##
Step #1 - "make-tests":       ^
Step #1 - "make-tests": *** ERROR: error creating deployment with gcluster for netapp-volumes-slurm.yaml

The other category of tests are bigger test cases. examples/netapp-volumes.yaml uses that approach. They have a dedicated test setup in tools/cloud-build/daily-tests/tests/ and are excluded from running in

cluster-toolkit/tools/validate_configs/validate_configs.sh

Line 133 in 6f755b4

    
           CONFIGS=$(find examples/ community/examples/ tools/validate_configs/test_configs/ docs/tutorials/ docs/videos/build-your-own-blueprint/ -name "*.yaml" -type f -not -path 'examples/dws-sample-workloads/*' -not -path 'examples/machine-learning/a3-megagpu-8g/*' -not -path 'examples/machine-learning/a3-ultragpu-8g/*' -not -path 'examples/machine-learning/build-service-images/*' -not -path 'examples/gke-a3-ultragpu/*' -not -path 'examples/gke-consumption-options/*' -not -path 'examples/gke-a4/*' -not -path 'examples/gke-a3-megagpu/*' -not -path 'examples/gke-a3-highgpu/*' -not -path 'examples/machine-learning/a4-highgpu-8g/*' -not -path 'examples/machine-learning/a4x-highgpu-4g/*' -not -path 'examples/machine-learning/a4x-maxgpu-4g-metal/*' -not -path 'community/examples/gke-tpu-v6e/*' -not -path 'community/examples/xpk-n2-filestore/*' -not -path 'examples/gke-a4x/*' -not -path 'examples/science/af3-slurm/*' -not -path 'examples/gke-h4d/*' -not -path 'community/examples/hpc-slinky/*' -not -path 'examples/gke-g4/*' -not -path 'community/examples/slurm-gke/*' -not -path 'examples/hpc-slurm-h4d/*' -not -path 'examples/machine-learning/a3-highgpu-8g/*' -not -path 'examples/netapp-volumes.yaml' -not -path 'examples/gke-tpu-7x/*' -not -path 'examples/gke-tpu-v6e/*' -not -path 'examples/gke-a4x-max-bm/*' -not -path 'examples/gke-tpu-v5e/*' -not -path 'examples/gke-g4-confidential/*' -not -path 'examples/gke-tpu-v5p/*' -not -path 'examples/gke-tpu-v4/*')

. Since NetApp Volumes functionality is already tested by netapp-volumes.yaml, netapp-volumes-slurm.yaml is not re-testing it again, but shows how it is configured using DNS. Having a basic verification through validate_configs.sh in a good thing, but I don't think it requires a big test with full SLURM attachment verification.

Does that make sense?

vikramvs-gg · 2026-09-15T07:22:54Z

/gcbrun

agrawalkhushi18 · 2026-09-15T19:35:50Z

Got it, thanks for the explaination @okrause .

okrause · 2026-09-16T10:18:54Z

Thank you @vikramvs-gg and @agrawalkhushi18 for your support. Very appreciated!

…udPlatform#6186)

okrause requested a review from a team as a code owner August 20, 2026 14:24

okrause requested review from agrawalkhushi18 and shubpal07 August 20, 2026 14:24

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okrause force-pushed the gcnv-multiple-ips branch from 69f3ea8 to 91cd3f7 Compare August 20, 2026 14:42

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siddhartha-quad assigned agrawalkhushi18 Aug 25, 2026

agrawalkhushi18 added the release-improvements Added to release notes under the "Improvements" heading. label Aug 26, 2026

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Comment thread modules/file-system/netapp-volume/variables.tf

agrawalkhushi18 assigned okrause and unassigned agrawalkhushi18 Sep 1, 2026

agrawalkhushi18 requested review from vikramvs-gg and removed request for shubpal07 September 1, 2026 05:50

okrause force-pushed the gcnv-multiple-ips branch from e05a0de to 539107b Compare September 1, 2026 12:32

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okrause force-pushed the gcnv-multiple-ips branch from 22c03c6 to 539107b Compare September 1, 2026 15:55

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agrawalkhushi18 enabled auto-merge (squash) September 14, 2026 08:02

NetApp Volumes: mount large-capacity volumes via Cloud DNS

fdb8a23

Large-capacity volumes and FlexCache expose multiple NFS endpoint IPs. Add volume dns_config and private-zone support so clients, including Slurm, mount by FQDN and use every endpoint. Update EDA and Slurm examples plus docs.

auto-merge was automatically disabled September 14, 2026 09:59
Head branch was pushed to by a user without write access

okrause dismissed stale reviews from agrawalkhushi18 and vikramvs-gg via fdb8a23 September 14, 2026 09:59

okrause force-pushed the gcnv-multiple-ips branch from 539107b to fdb8a23 Compare September 14, 2026 09:59

agrawalkhushi18 approved these changes Sep 15, 2026

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agrawalkhushi18 enabled auto-merge (squash) September 15, 2026 19:38

vikramvs-gg approved these changes Sep 16, 2026

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agrawalkhushi18 merged commit 9df9fe6 into GoogleCloudPlatform:develop Sep 16, 2026
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okrause deleted the gcnv-multiple-ips branch September 16, 2026 10:18

ep-nag pushed a commit to nagconsulting/cluster-toolkit that referenced this pull request Oct 5, 2026

NetApp Volumes: mount large-capacity volumes via Cloud DNS (GoogleClo…

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…udPlatform#6186)

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