AR750 DIY VPN status indicator

Routers
5

Thanks for your feedbacks. I set aside the original 2G and 5G wlan status indication and use them for my purposes now to indicate internet and vpn connectivity (led 2G is on, if internet is available and led 5G is on, if vpn is up and the remote network is reachable). And here is, how it works:

  1. set LED functions to „none“ in the glinet admin web tool. The leds should then be switched off.
  2. upload the two scripts below (e.g. to /usr/bin/). If sftp does not work you can use in your ssh console: cat > full-path-and-filename and simply copy and paste the content of the script (use ctrl-d to get back to your prompt).:point_up: Be careful, the cat > command overwrites everything of the file. Check better twice the correct spelling of the filename before you enter into the command :wink:
  3. chmod u+x full-path-and-filename
  4. now you can check the scripts by calling them without arguments.
  5. to let them call frequently by the system add the cron configuration with the glinet admin web tool or crontab -e

Note: the vpn check also restarts the openvpn process and reloads the network configuration. Maybe not necessary in a stable and static vpn environment but I have faced vpn problems, after the remote side has changed their IP address.

The scripts are modifications from what I have found this in this forum. And I am not sure, if the 8.8.8.8 (google dns) actually works worldwide.

And here are the scripts:

inet_check.sh

#!/bin/sh
#
# crontab -e
# */1 * * * * test -x /usr/bin/inet_check.sh && /usr/bin/inet_check.sh
#

inet_led=/sys/devices/platform/leds-gpio/leds/gl-ar750:white:wlan2g/brightness


nc -z -w 5 8.8.8.8 53  >/dev/null 2>&1
online=$?
if [ $online -eq 0 ]; then
  logger -t inet_check internet is online.
  echo 1 > $inet_led
else
  logger -t inet_check internet is offline.
  echo 0 > $inet_led
fi

vpn_check.sh

#!/bin/sh
#
# crontab -e
# */1 * * * * test -x /usr/bin/vpn_check.sh && /usr/bin/vpn_check.sh
#

vpn_led=/sys/devices/platform/leds-gpio/leds/gl-ar750:white:wlan5g/brightness

# Should openvpn already be in operation? If not, nothing to do, exit.
enabled=$(uci get glconfig.openvpn.enable)
vpn_client=$(uci get network.ovpn)    # removed when startvpn stopped explicitly


if [ "$enabled" != "1" ] || [ "$vpn_client" != "interface" ]; then
  echo 0 > $vpn_led
  exit 0
fi

# First hop should be to the internal VPN gateway (10.8.0.1) if VPN up. You might have a different first hop.
# If we're going through VPN then all is well, do nothing.
first_hop=$(traceroute 8.8.8.8 2>&1 | head -2 | tail -1 | awk '{print $2}')

if [ "$first_hop" == "10.8.0.1" ]; then
  logger -t VPN_check VPN is fine.
  echo 1 > $vpn_led 
  exit 0
fi

echo 0 > $vpn_led 

#restart
logger -t VPN_check RESTART openvpn
killall openvpn 2>/dev/null
ovpn=$(uci get glconfig.openvpn.ovpn)
/usr/sbin/openvpn "$ovpn" &
(sleep 1; /etc/init.d/network reload) &
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