checkId: check.docker.apiversion plugin: stellaops.doctor.docker severity: warn tags: [docker, api, compatibility]

Docker API Version

Doctor check check.docker.apiversion — for operators and DevOps engineers confirming that the Docker daemon exposes an API version new enough for the container, image, and network features Stella Ops depends on.

What It Checks

Validates that the Docker API version meets minimum requirements for Stella Ops. The check connects to the Docker daemon (using Docker:Host configuration or the platform default) and queries the API version via System.GetVersionAsync().

API Version	Result
Below 1.41	`warn` — below minimum required
Between 1.41 and 1.43	`warn` — below recommended
1.43 or higher	`pass`

The minimum API version 1.41 corresponds to Docker Engine 20.10+. The recommended version 1.43 corresponds to Docker Engine 23.0+.

Evidence collected includes: API version, Docker version, minimum required version, recommended version, OS, build time, and git commit.

Default Docker host:

Linux: unix:///var/run/docker.sock
Windows: npipe://./pipe/docker_engine

Why It Matters

Stella Ops uses Docker API features for container management, image inspection, and network configuration. Older API versions may not support required features such as:

BuildKit-based image builds (API 1.39+).
Multi-platform image inspection (API 1.41+).
Container resource management improvements (API 1.43+).

Running an outdated Docker version also means missing security patches and bug fixes.

Common Causes

Docker Engine is outdated (version < 20.10)
Docker Engine is functional but below recommended version (< 23.0)
Using a Docker-compatible runtime (Podman, containerd) that reports a lower API version
Docker not updated after OS upgrade

How to Fix

Docker Compose

Update Docker Engine to the latest stable version:

# Ubuntu/Debian
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io

# RHEL/CentOS
sudo yum update docker-ce docker-ce-cli containerd.io

# Verify version
docker version

Bare Metal / systemd

# Check current version
docker version

# Update Docker
curl -fsSL https://get.docker.com | sh

# Restart Docker
sudo systemctl restart docker

# Verify
docker version

Kubernetes / Helm

Update the container runtime on cluster nodes. The method depends on your Kubernetes distribution:

# Check node runtime version
kubectl get nodes -o wide

# For kubeadm clusters, update containerd on each node
sudo apt-get update && sudo apt-get install containerd.io

# Verify
sudo crictl version

Verification

stella doctor run --check check.docker.apiversion

check.docker.daemon— verifies Docker daemon is running (prerequisite for version check)
check.docker.socket— verifies Docker socket is accessible

See the Doctor reference for the full check catalog, CLI usage, and export bundles.