Troubleshooting

The file dropdown is empty

• The plugin only lists regular files ending in .log inside OctoPrint's log folder (usually ~/.octoprint/logs).
• Check that the OctoPrint user can read that folder.

Streaming shows no new lines

• The tailer starts at the end of the file: only lines written after the stream starts appear (plus up to 100 initial context lines).
• New lines are delivered in batches once per poll interval (stream_poll_interval_s, default 5 s) — short delays are expected.
• Rotated and truncated log files are picked up automatically; if a stream ever looks stuck, stop and restart it.

Search returns an error

Status	Meaning	Fix
400	Invalid filename, level, or paging	Check query parameters.
403	File outside the log folder	Only plain filenames in the log folder work.
404	File does not exist	Refresh the file list.
413	File larger than 1 GiB	Rotate/trim the log file.
429	More than 10 searches per minute	Wait a moment; the limit is per client address.

Alerts do not appear

• Check alerts_enabled and that the level is listed in severity_triggers (defaults: WARNING, ERROR, CRITICAL).
• In mode selected, only files in alerts_monitored_logs are watched — the Alert monitor status panel in the plugin settings shows which files are currently active.
• Alert toasts additionally require enable_notifications.

Getting more information

1. Enable debug mode in the plugin settings.
2. Use Write test entries in the settings to generate one log entry per severity and verify the whole pipeline.
3. Check octoprint.log for entries from octoprint.plugins.logmonitor — including [SECURITY] entries for rejected filenames or rate limits.

Still stuck? Open a GitHub issue with your OctoPrint version, plugin version, and relevant log excerpts.