Hi all,

My need is to run script when wwan0 interface obtains IP address.
How do I perform it?
Thanks ahead.

Ubuntu 14.04.1 LTS

I gotta be honest with you, I had this same conundrum a few years ago and I solved it with brute force which was to have another script or program run for a long, but finite period of time, say 2 minutes and poll the interface status, and by observing the status, I'd be able to detect if an address was negotiated versus not. Then following that I gave status back to my GUI, but similarly I could've then invoked a script. I did nothing more than parsed the output of ifconfig for that interface to determine if a valid address was set for that interface. Say maybe did that once every 5 seconds for a count of 24 iterations before I gave up.

If you use NetworkManager, then perhaps you could use a script in /etc/NetworkManager/dispatcher.d/ that checks the interface name and the appropriate dhcp change action (either v4 or v6) to signal whether further commands should be run. See 'man NetwrkManager' for details.
As an example, here is the script I use to change firewall rules depending on the interface in use on my netbook. http://www.linuxquestions.org/questi...1/#post4579765

To know the ip address of all network interfaces in your system just run:

ip a

And use shell grep awk to parse it.