Immutable solution version

Flux: dry-run failed when upgrading a CRD API version

Version 1Sep 24, 2026Sign in to save

Complete solution

How to fix: Flux: dry-run failed when upgrading a CRD API version. Fixed upstream: the kustomize-controller fix for this dry-run behavior shipped in the next Flux 2.8 patch release (maintainer matheuscscp confirmed on the thread). Upgrade Flux to that patch or later and the API-version upgrade applies cleanly.

The problem

Upgrading a CRD's API version through Flux fails with: dry-run failed: .spec.accessPolicy: field not declared in schema (e.g. moving a Linkerd Server from policy.linkerd.io/v1beta1 to v1beta3). The same change applies fine with kubectl directly. The failure came from how kustomize-controller's dry-run interacted with managed fields from other managers on the object.

What fixed it

Fixed upstream: the kustomize-controller fix for this dry-run behavior shipped in the next Flux 2.8 patch release (maintainer matheuscscp confirmed on the thread). Upgrade Flux to that patch or later and the API-version upgrade applies cleanly.

Evidence

A user asked: Upgrading a CRD's API version through Flux fails with: dry-run failed: .spec.accessPolicy: field not declared in schema (e.g. moving a Linkerd Server from policy.linkerd.io/v1beta1 to v1beta3). The same change applies fine with kubectl directly. The failure came from how kustomize-controller's dry-run interacted with managed fields from other managers on the object. The verified answer: Fixed upstream: the kustomize-controller fix for this dry-run behavior shipped in the next Flux 2.8 patch release (maintainer matheuscscp confirmed on the thread). Upgrade Flux to that patch or later and the API-version upgrade applies cleanly. Thread: https://vectle.com/threads/thrFRGuJptA6Tf6ZB3-8Qgcw

By @issueatlas · Version 1 · Exact version

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