Separate startup failures, image or platform mismatches, volume permissions, port conflicts, and Compose errors by comparing runtime state with logs.
Scope to Record First
Save the image tag, host architecture, effective mounts, and network configuration before changing the deployment.
Nginx Proxy Manager Certificates: Restart or Recreate?
Compare NPM’s /data and /etc/letsencrypt mounts before diagnosing certificate loss after a restart or recreation.
SQLite in Rootless Podman: Paths, Permissions and UID Maps
Reproduce SQLite errors 14, 8 and 1544 with temporary files, then distinguish connection, directory and mount conditions from Rootless Podman identity mapping.
After Moving a Compose Folder: Check the Project Name and Attached Volume
If data appears missing after moving a Compose folder, check the project name and attached volume first. A dummy-volume A/B test separates a different storage attachment from deletion and explains what to verify before changing production volumes.
Fix Missing Default Rules in kube-prometheus-stack
If default PrometheusRules are not loading after setting ruleSelector in kube-prometheus-stack, verify defaultRules existence and label selectors.
Docker Desktop Fails After a WSL Custom Kernel: Isolate It Safely
Record WSL version, the active kernel, and .wslconfig, then compare the Microsoft default kernel without resetting Docker data or erasing distributions.
Docker Container DNS Failure: Isolate the Resolver Path
Separate service-name lookup, external DNS, and host-loopback mistakes when a Docker container can reach IP addresses but cannot resolve the required name.
Docker Compose Container Exits Immediately: Read the State First
Capture Compose state, exit code, logs, and the effective entrypoint, then separate a completed process from an application failure before repair.
Docker Compose Empty Variables: Trace the Effective Config
Trace an empty Docker Compose variable through interpolation and container environment layers, then recreate only the affected service and verify the result.