Logs and Journald

Logs and Journald

When an Uptrakit daemon runs under systemd with its output connected to the journal, it logs in native journald format: clean messages, real priorities, and structured fields. In a terminal or with redirected output it prints classic text lines instead. Selection is automatic; see below for the override.

Reading logs

journalctl -u uptrakit                      # clean one-line messages
journalctl -u uptrakit -p warning           # warnings and errors only
journalctl -u uptrakit -p notice            # INFO and up (DEBUG excluded)
journalctl -u uptrakit -o verbose           # full structured view (PRIORITY, TARGET, fields)
journalctl -u uptrakit F_HOST_ID=<uuid>     # filter by a structured field

Event fields such as host_id are stored as indexed journal fields with an F prefix (F_HOST_ID), not inside the message text. Plain grep host_id= over journalctl output (and journalctl -g, which searches MESSAGE only) will no longer match them — use the field-filter form above.

Forcing a format

Set UPTRAKIT_LOG_FORMAT to auto (default), text, or journald. On a deployed unit, use a systemd drop-in so the setting survives reinstalls (the installer rewrites /etc/systemd/system/uptrakit.service on every run — direct edits to the unit file are lost):

mkdir -p /etc/systemd/system/uptrakit.service.d
printf '[Service]\nEnvironment=UPTRAKIT_LOG_FORMAT=text\n' \
  > /etc/systemd/system/uptrakit.service.d/logging.conf
systemctl daemon-reload && systemctl restart uptrakit

Caveats

• StandardOutput=journal+console: stdout still identifies as the journal, so journald mode activates and the console tee stops showing log lines. Use the text override if you need the console copy.
• Structured entries store more bytes per event than text lines. At high verbosity this shortens the journal's effective retention window — check with journalctl --disk-usage and prefer moderate verbosity in production.