A systemd-based link activity monitor for ASL3 (AllStarLink 3) nodes with configurable inactivity timeouts, blackout windows, scheduled resets, and more.
When your repeater node has been inactive (no local RF activity or new node connections) for a configurable period, the monitor plays a warning announcement and then resets the node — disconnecting any linked nodes and reconnecting to your configured nodes. It provides the same core functionality as the native lnkactenable/lnkactmacro timer built into ASL3, but with significantly more control over when and how resets occur.
Activity that resets the inactivity timer:
- Local RF activity (kerchunks) detected on your node
- A new node connecting to or from your node (requires connection logging)
Features:
- Configurable inactivity timeout
- TTS or pre-recorded audio warning before reset
- Skip reset if only permanent/hub nodes are connected
- Scheduled blackout windows (suppress resets during nets, etc.)
- Scheduled forced resets at configured times of day
- Reconnect to multiple nodes after reset
- Enable/disable monitor via
lnkactcommand (for use by other scripts) - Daily reset counter logged
- Asterisk availability check before each cycle
- Connection log rotation detection
- Separate config file survives script updates
- ASL3 on Debian 12
asl-tts(included with ASL3) if using TTS warning mode- Connection logging (optional but recommended) — see ASL3-Connection-Log
Run the following command as root or with sudo for both fresh installs and updates:
bash <(curl -fsSL -H "Cache-Control: no-cache" https://raw.githubusercontent.com/N6LKA/ASL3-Link-Activity-Monitor/main/install.sh)Fresh install: The installer will prompt you for your node number and basic settings, create the configuration file, and start the service.
Existing install detected: The installer will stop the service, back up the existing script, download the latest version, and restart. Your lnkact-monitor.conf is never modified. If an update adds new configuration variables, they will be automatically appended to your conf file with default values on the next service start.
Tip: For initial testing, set
INACT_TIMEOUT=180in the conf file so you can verify the warning and reset fire within a few minutes, then change it back to your desired value.
ASL3 does not have a native connection log. To enable connection-based timer resets, install the companion logging scripts first:
👉 https://github.com/N6LKA/ASL3-Connection-Log
If you skip this, set CONNECT_LOG="" in the conf file. The monitor will still work using RF activity (kerchunk counter) only.
Important: The connection log file must be owned by the
asteriskuser or the logging scripts will not be able to write to it. If you ever recreate or replace the file manually (e.g. during log rotation testing), restore ownership with:chown asterisk:asterisk /var/log/asterisk/connectlog chmod 644 /var/log/asterisk/connectlog
All settings are in /etc/asterisk/scripts/lnkact-monitor/lnkact-monitor.conf. After making changes, restart the service:
systemctl restart lnkact-monitor| Variable | Default | Description |
|---|---|---|
NODE |
(required) | Your ASL3 node number |
INACT_TIMEOUT |
900 |
Seconds of inactivity before reset (900 = 15 min) |
POLL_INTERVAL |
2 |
How often to check activity (seconds) |
WARN_MODE |
tts |
Warning mode: tts, file, or none |
WARN_TTS_TEXT |
see conf | TTS text spoken as warning |
WARN_AUDIO |
see conf | Path to pre-recorded warning file (no extension) |
WARN_LEAD |
30 |
Seconds before reset to play warning |
WARN_OFFSET_TTS |
7 |
Extra seconds for TTS processing time |
WARN_OFFSET_FILE |
7 |
Extra seconds for file playback time |
CONNECT_LOG |
/var/log/asterisk/connectlog |
Path to connection log, or blank to disable |
PERMANENT_NODES |
(blank) | Space-separated hub/permanent nodes — reset skipped if only these connected |
BLACKOUT_START |
(blank) | Blackout window start HH:MM 24hr — resets suppressed |
BLACKOUT_END |
(blank) | Blackout window end HH:MM 24hr |
SCHEDULED_RESETS |
(blank) | Space-separated HH:MM times to force a daily reset |
USE_TELEMETRY |
yes |
Wrap reset in telemetry off/on (cop 34/35) |
DISCONNECT_ALL |
yes |
Disconnect all nodes before reconnecting |
RECONNECT_NODES |
(blank) | Space-separated nodes to reconnect after reset |
ANNOUNCE |
yes |
Play TTS announcement after reset |
ANNOUNCE_TEXT |
Connection Reset |
TTS text spoken after reset |
Suppress resets during your Monday night net (7 PM – 9 PM):
BLACKOUT_START="19:00"
BLACKOUT_END="21:00"
Midnight-spanning windows are supported (e.g. 22:00 to 06:00).
Force a reset every morning at 6 AM and every evening at 4 PM:
SCHEDULED_RESETS="06:00 16:00"
Scheduled resets always fire regardless of activity or connected nodes. The configured warning plays first.
Other scripts (such as news or scheduler scripts) can enable or disable the monitor without stopping the service:
lnkact disable # Suppress resets (e.g. while playing news)
lnkact enable # Resume normal operation
lnkact status # Show current status, uptime, resets today, etc.The lnkact command is available system-wide after installation.
systemctl start lnkact-monitor
systemctl stop lnkact-monitor
systemctl restart lnkact-monitor
systemctl status lnkact-monitor
journalctl -u lnkact-monitor -f| File | Location | Description |
|---|---|---|
lnkact-monitor.sh |
/etc/asterisk/scripts/lnkact-monitor/ |
Main script (do not edit) |
lnkact-monitor.conf |
/etc/asterisk/scripts/lnkact-monitor/ |
User configuration |
lnkact.sh |
/etc/asterisk/scripts/lnkact-monitor/ |
Control script (do not edit) |
lnkact-monitor.service |
/etc/systemd/system/ |
Systemd service definition |
lnkact |
/usr/local/bin/ |
Symlink to lnkact.sh for system-wide access |
The monitor polls every few seconds checking for two types of activity: local RF kerchunks via rpt stats (which only increments on local RF, not linked node audio), and new entries in the connection log. It uses RPT_ALINKS/RPT_NUMALINKS rather than RPT_LINKS to get an accurate count of directly connected nodes — this avoids false triggers from nodes that appear connected through an intermediary node but are not directly linked, which would otherwise prevent the reset from ever firing.
This monitor was originally written after the native lnkactenable/lnkactmacro timer stopped working on one particular ASL3 node — though the native function works fine on other nodes and setups, so your mileage may vary. What started as a workaround quickly grew into a more feature-rich replacement, adding blackout windows, scheduled resets, multi-node reconnect, and more. Even if your native timer is working, this monitor may be worth considering if you want more control over when and how resets happen.
If this project has been useful to you, please consider supporting its development!
GNU General Public License v3.0 (GPLv3) — Copyright 2026 Larry K. Aycock (N6LKA)
See LICENSE for details.