It is fairly simple to use once you know how to use it. However, the tricky thing is that by default it doesn't seem to be active or listen on any interface on manually specified.
How To Install ifplugd
First we install ifplugd
sudo apt install ifplugd
Let's enable it on our desired device(s)
vi /etc/default/ifplugd
set this line as so:........
This is mainly the case on Centos but applies to other distros and situations. If you are running programs in the background with the &, at least in Centos it is usually not honored and if you quit or are disconnected the backgrounded programs will be sent sighup and be shut down.
The simplest way around this instead of using & is to start any programs or commands with "nohup"
Eg.
nohup yourscript.sh........