Docker Engine Ubuntu 26.04 rootful¶

Native Ubuntu 26.04 docker.io package with rootful Docker daemon for isolated compatibility tests

Image: ghcr.io/strukturpiloten/docker-ubuntu-26.04-rootful
Declared image version: v1.0.0
Family: Docker Engine
Architecture: amd64, arm64
Inner mode: rootful

Declared runtime base: docker.io/library/ubuntu:26.04@sha256:da6fc2be547864451aa253836dd926da33623312df4a9a243e35dc877c378a78

Image source and metadata · GHCR package · Detailed guide

Choose and inspect¶

The distribution selects the installed engine package at build time. Inspect the published image's component manifest or SBOM for its exact revision.

Declared tags: v1.0.0, v1.0, v1, main, latest. These are publication policy aliases, not proof that any tag exists in GHCR. Even the exact SemVer tag can move after a reviewed rebuild.

Registry status: observed; checked at 2026-09-28T10:16:33.771036+00:00.

Observed latest index digest: sha256:d5e144ed6127c7819311c2f4f2935a06c3e1b14fdd3e7e304635aef371e5ee82.

Pull the observed immutable artifact:

podman pull ghcr.io/strukturpiloten/docker-ubuntu-26.04-rootful@sha256:d5e144ed6127c7819311c2f4f2935a06c3e1b14fdd3e7e304635aef371e5ee82

For an isolated Linux nested-Docker test, the outer Podman boundary runs rootfully and privileged. Use a trusted runner and keep its image store separate from other tests:

sudo podman run --rm --detach --name nested-docker --privileged --device /dev/fuse --security-opt label=disable ghcr.io/strukturpiloten/docker-ubuntu-26.04-rootful@sha256:d5e144ed6127c7819311c2f4f2935a06c3e1b14fdd3e7e304635aef371e5ee82
ready=0
for attempt in $(seq 1 30); do
  if sudo podman exec nested-docker docker info >/dev/null 2>&1; then ready=1; break; fi
  sleep 2
done
if [ "$ready" -eq 1 ]; then sudo podman exec nested-docker docker info; else sudo podman logs nested-docker; fi
sudo podman stop nested-docker
test "$ready" -eq 1

This fixture does not use the host Docker socket. Read the detailed guide for nested workloads.

Support and runtime contract¶

Lifecycle: maintained; admission: isolated-test; review after: 2026-10-27.

Vendor package revisions can advance with repository updates; image shares runner kernel and host security policy.

Declared runtime profiles: docker. Declared test settings are in the metadata source. Admission is policy, not evidence of a passed test.

Declared runtime test contract:

{
  "docker": {
    "mode": "rootful",
    "nestedRuntime": true,
    "outerPrivilege": "privileged"
  }
}

Registry aliases and history¶

Aliases resolved to the observed current digest: latest, main, v1, v1.0, v1.0.0.

Listed without digest resolution: run-36346260768-1-sha-0b136a13a8bb612d91960ae5d07e72f449c89ec1, sha-0b136a13a8bb612d91960ae5d07e72f449c89ec1, sha256-9ad31ce0c26a02f4202c831e3ba0408586d2ac61b703a25e57c805d476922b88, sha256-d5e144ed6127c7819311c2f4f2935a06c3e1b14fdd3e7e304635aef371e5ee82, sha256-daeea114052586fb2f48d8a85330d84edec091fb356e9c9d8447f4e7d6a27228.

Evidence and timestamps¶

Matching release asset verified the build record and per-architecture runtime and scan evidence. Signature and provenance remain unverified in this snapshot.

Maintenance release · Evidence asset

GitHub package activity can include signatures and attestations; it does not identify when the current runnable image was published. A registry observation is a point-in-time check; mutable tags may move afterward. Use the immutable digest and maintenance evidence for an audit.