Kubernetes upgrades are one of the most critical operations in cluster management. Done wrong, they cause downtime. Done right, they're seamless.
Before You Upgrade
- Review the Kubernetes changelog for breaking changes in your target version
- Check all your workloads support the target version (check API deprecations)
- Ensure your CNI, CSI, and other add-ons are compatible
- Take etcd snapshots and verify restore works
- Test the full upgrade in a staging cluster first
- Review your PodDisruptionBudgets for critical workloads
The Upgrade Process
1. Upgrade the control plane first (one minor version at a time) 2. Verify control plane is healthy before touching nodes 3. Upgrade worker nodes one at a time — drain, upgrade, uncordon 4. Verify workloads are healthy after each node 5. Update kubectl, Helm, and other tooling to match
On EKS, AKS, and GKE
Managed K8s services simplify control plane upgrades. On EKS, use managed node group rolling updates. Set max-unavailable to 1 and use PodDisruptionBudgets to prevent service interruption.
Common Pitfalls
- Skipping minor versions (always upgrade one at a time: 1.28 → 1.29 → 1.30)
- Not checking API deprecations before upgrading
- Forgetting to upgrade cluster add-ons after the control plane
InfraOpex Kubernetes Upgrade Service
We handle Kubernetes upgrades across EKS, AKS, GKE, and on-prem clusters with proven zero-downtime strategies. Contact us to plan your next upgrade.