Q:

what is the PPA's OpenPGP ID?

I'm creating a LiveCD from this guide and came across a line I do not understand:
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 12345678 
#Substitute "12345678" with the PPA's OpenPGP ID.

wondered if anyone can explain what should I substitue 12345678 with and how to obtain it

A:

The information is listed on the ppa page in launchpad
Sample screenshot :

So , using the above as an example
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys A9E345C0

See PPA FAQ and Ubuntu wiki secure apt for details

