What's New in kind v0.33.0: Kubernetes 1.37 Default and Key Fixes

💡 Quick Answer: kind v0.33.0 bumps the default node image to Kubernetes 1.37.0 (pinned by sha256 digest), fixes Docker client proxy handling and load-balancer config persistence across restarts, and improves local-path-provisioner tolerations. No new user-facing features beyond dependency bumps.

The Problem

Teams running kind for local development or CI need up-to-date Kubernetes node images and bug fixes without re-learning a new workflow each release. Prior versions defaulted to older Kubernetes minors and had issues with Docker proxy configs not being respected and load balancer (HAProxy/envoy CDS/LDS) config resetting on container restart.

The Solution

Upgrade the kind CLI binary to v0.33.0 and, if you pin node images explicitly in your cluster config, update to the new kindest/node digests. The default cluster created with no --image flag now provisions Kubernetes 1.37.0.

Whats New

Breaking Changes

• Default node image changed to:

kindest/node:v1.37.0@sha256:a1ed56cfb0e7b93589bdf97c8cd566405a265939e3620fc4f5de89adff580ae5

Any automation relying on the previous default minor version will now get 1.37.0 unless an image is pinned explicitly.

New Features

• Assorted dependency updates (no new CLI features called out in this release).

Fixes

• Respect Docker client proxy config for docker-backed nodes (#4192).
• Preserve external load balancer CDS/LDS configuration across container restarts (#4195) — relevant for multi-control-plane (HA) kind clusters.
• Improve local-path-provisioner helperPod tolerations (#4210).
• Assorted documentation fixes.

Pre-built node images for this release

Note: Always pin by @sha256 digest. Tag-only references are not guaranteed to resolve to the release-specific build until kind changes its tagging scheme. Images support amd64 and arm64 — use the digest matching your host architecture (see kind#2718).

Upgrade Steps

Install or upgrade the kind binary (Linux amd64 example):

curl -Lo ./kind https://kind.sigs.k8s.io/dl/v0.33.0/kind-linux-amd64
chmod +x ./kind
sudo mv ./kind /usr/local/bin/kind
kind version

For macOS via Homebrew:

brew upgrade kind

Create a new cluster on the default (1.37.0) node image:

kind create cluster --name demo

Or pin an explicit image/digest in a cluster config:

cat <<'EOF' > kind-config.yaml
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
 image: kindest/node:v1.37.0@sha256:a1ed56cfb0e7b93589bdf97c8cd566405a265939e3620fc4f5de89adff580ae5
- role: worker
 image: kindest/node:v1.37.0@sha256:a1ed56cfb0e7b93589bdf97c8cd566405a265939e3620fc4f5de89adff580ae5
EOF

kind create cluster --name demo --config kind-config.yaml

Existing clusters are not upgraded in place — kind does not support live Kubernetes version upgrades. Delete and recreate if you need the new default:

kind delete cluster --name demo
kind create cluster --name demo

Verify

kind version
# kind v0.33.0 go1.2x linux/amd64

kubectl cluster-info --context kind-demo
kubectl get nodes -o wide
# CONTAINER-RUNTIME column / image should reflect v1.37.0 nodes

docker ps --filter label=io.x-k8s.kind.cluster=demo --format '{{.Image}}'

If you run multi-control-plane (HA) clusters behind the built-in load balancer, restart a control-plane container and confirm routing still works (regression fixed by #4195):

docker restart demo-control-plane2
kubectl get nodes

Common Issues

• Pulling the wrong architecture image: if you manually specify an image digest, ensure it matches your host CPU architecture (amd64/arm64); kind does not cross-build automatically.
• CI pipelines pinned to old Kubernetes minor break: if automation assumed the previous default minor, pin the image explicitly as shown above rather than relying on kind’s shifting default.
• local-path-provisioner pods pending: if you customized tolerations on nodes, verify the updated helperPod tolerations (#4210) still match your node taints.

Best Practices

• Always pin node images by @sha256 digest in CI and shared dev environments for reproducibility.
• Track the kind releases page and bump the default Kubernetes version deliberately rather than implicitly via kind CLI upgrades.
• Recreate clusters rather than attempting in-place Kubernetes version upgrades — kind clusters are designed to be ephemeral.
• Check Docker proxy environment variables (HTTP_PROXY, HTTPS_PROXY, NO_PROXY) are correctly picked up now that #4192 is fixed, especially in corporate network setups.