Troubleshooting
Golden rule
- Reproduce, observe logs/metrics, change one thing, verify.
Common web issues
502 Bad Gateway
- Check upstream process is running (systemd/PM2).
- Check Nginx upstream port and firewall rules.
TLS certificate errors
- Confirm DNS points to the server.
- Renew cert and reload Nginx.
Resource pressure
- Disk: check logs size, rotate, prune images/volumes.
- RAM: look for OOM kills; add swap or tune workers.
Next pages
Page changelog
Last updated
- 2026-01-18—Initial or baseline update for this page.
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