Fleet Upgrade Verification

Reports every GKE cluster's control-plane and node-pool versions against a target version or each cluster's release-channel default, naming the members that lag and by how many minors; run again during a rollout, it shows which members started, completed or stalled since the previous run; with --readiness, it also grades each member on what would stop the upgrade, naming drain-blocking PodDisruptionBudgets, fail-closed admission webhooks in the upgrade's path or able to refuse the control plane's bootstrap RBAC writes (ClusterRoles and ClusterRoleBindings; Roles and RoleBindings in kube-system and kube-public) with an unreachable backend, maintenance exclusions and windows, node-pool version skew, and what the per-entry rules of the upgrade-failure catalogue find, each a blocker or a risk that does not block (a zonal control plane is one). Scans the linked GitOps repositories' manifests for apiVersions the target removes, with each hit's replacement. Read-only against GCP, the clusters and Git, from gcloud container, kubectl get and repository reads, plus the audit log through gcloud logging read when a registered rule reads it, keeping only its own record of each run and per-member kubeconfig files; the executed counterpart to gke-upgrades' advice.

mkdir -p ~/.claude/skills/fleet-upgrade-verification
curl -L https://claudskills.com/skills/fleet-upgrade-verification/SKILL.md \
  -o ~/.claude/skills/fleet-upgrade-verification/SKILL.md

@misc{fleet-upgrade-verification-2026,
  author    = {gke-labs},
  title     = {Fleet Upgrade Verification [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/fleet-upgrade-verification/}
}