This is the best tutorial I have found that allowed me to install FreePBX on an Ubuntu 14.04 instance on an Amazon AWS instance. I tried a few and this one really did work for me after following all of the steps and exercising patience.
http://wiki.freepbx.org/display/HTGS/Installing+FreePBX+12+on+Ubuntu+Server+14.04+LTS.
FreePBX is a very useful tool for setting up a free VOIP system for cheap telephony over the Internet. But it must be installed from source so that everything works well together. The only PPA I could find was for Ubuntu Hardy and this is obviously far too old to be practical or secure.
Why not save time and effort – simply order a vps hosting package here and select elastix from the OS drop-down menu. Elastix 2.4 comes with freepbx already pre-installed so all you have to do is execute:
/etc/init.d/elastix-firstboot start
set the passwords and you are ready to go.
I’m using their SSD 4 vps hosting plan with elastix (and freepbx) for more than a year now, and I have had practically no issues so far.