ipforwarder
At every change of IP sends the new address through telegram-send.
This little scripts allows to keep you updated to the IP addresses of all your servers through the use of telegram-send.
I execute it through cron setting my crontab to:
@reboot . ~/opt/ipforwarder/ipforwarder.sh > /dev/null
0 * * * * . ~/opt/ipforwarder/ipforwarder.sh > /dev/null
In this way the script executes at every reboot and every hour.
What this script does is to wait till the server is connected to a router, then asks for the WAN ip address through the API. https://api.ipify.org/\?format\=txt
If it detects a new IP address it notifies the user, otherwise it doesn't. The old ip address is stored in the log file.
Tested on MAC OSX.