Ubuntu 22.04 LTS – Docker daemon fails to start after cgroup configuration drift – Fix & Prevention

📖 ~1 min read

Table of contents

1. Symptom & Impact
2. Environment & Reproduction
3. Root Cause Analysis
4. Quick Triage
5. Step-by-Step Diagnosis
6. Solution – Primary Fix
7. Solution – Alternative Approaches
8. Verification & Acceptance Criteria
9. Rollback Plan
10. Prevention & Hardening
11. Related Errors & Cross-Refs
12. References & Further Reading

Symptom & Impact

Docker service enters failed state and container workloads cannot start.

Environment & Reproduction

Common after manual daemon.json edits or runtime upgrades.

Root Cause Analysis

Mismatch between systemd cgroup mode and configured Docker cgroup driver prevents daemon initialization.

Quick Triage

Inspect recent daemon logs and current cgroup mode quickly.

Step-by-Step Diagnosis

Validate daemon.json syntax and runtime compatibility with host kernel/cgroup setup.

Solution – Primary Fix

Set Docker to systemd cgroup driver where required and restart daemon cleanly.

Solution – Alternative Approaches

If Kubernetes is not used, keep defaults but remove conflicting custom cgroup overrides.

Verification & Acceptance Criteria

Docker daemon stays active and sample containers start/stop successfully.

Rollback Plan

Restore previous daemon.json from backup and restart docker if behavior worsens.

Prevention & Hardening

Standardize daemon.json via configuration management and test after engine upgrades.

Related Errors & Cross-Refs

Related to containerd plugin failures and bridge network initialization errors.

Related tutorial: View the step-by-step tutorial for Ubuntu 22.04 LTS.

View all Ubuntu 22.04 LTS tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Docker Engine and Ubuntu cgroup documentation.