What Docker’s “unhealthy” status means, why it happens, and how to debug failing containers with clarity and control.

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Docker's 'unhealthy' status indicates that health checks are failing even though the container is still running. The guide explains how to debug unhealthy containers by inspecting health logs, testing health check commands directly, and identifying common causes like application crashes, broken dependencies, resource exhaustion, or misconfigured health checks. It covers setting up proper health checks in Dockerfiles and docker-compose, tuning parameters like interval and timeout, and implementing automatic restart strategies using tools like autoheal or custom scripts.

Docker Status Unhealthy: What It Means and How to Fix It

Health Check Setup in Docker and Docker Compose

What to Do When a Container Turns Unhealthy