ST-2026-142 · Runtimes & execution environments
GKE 1.35 introduces a CNI specification floor that excludes Cloud Service Mesh CNI 1.20.x
GKE version 1.35.1-gke.1516000 and later require CNI specification 1.1.0; Cloud Service Mesh CNI 1.20.x is incompatible and must be upgraded to 1.23.x or later before the GKE upgrade.
Previous state
Clusters could run older Cloud Service Mesh CNI releases that implement an earlier CNI specification.
Current state
Upgrading to the named GKE build or later requires CNI 1.1.0 and therefore a compatible Cloud Service Mesh CNI release.
Affected users
Who needs to care
GKE clusters using Cloud Service Mesh CNI 1.20.x or another plugin below the new specification floor.
Required response
What to do
Upgrade the mesh CNI to 1.23.x or later before moving the cluster to the affected GKE version, or delay the GKE upgrade.
Evidence boundary
What the source does not prove
The boundary is version-triggered rather than a universal calendar shutdown and does not say all GKE 1.35 builds are affected.
Lifecycle history
Dated event sequence
- Compatibility guidance updated
Google documented the GKE build threshold and compatible mesh CNI versions.
Evidence ledger
First-party sources
- 01Google Cloud — Troubleshoot managed Cloud Service Mesh CNI
Official compatibility and remediation guidance · 2026-06-29
Open official source ↗