I wanted to make an extra warning to everyone that Ubuntu LTS 14.04 is no longer being supported by Canonical, who is the main player in programming and putting together Ubuntu. Any further security patches or nuances/bugs will only be covered if you pay Canonical $75 for their Ubuntu Advantage subscription ( https://www.ubuntu.com/support ) for their Extended Security Maintenance (ESM).
A major disadvantage is that there is little to no motivation for the community to look for security issues and patch them in Ubuntu 14.04, since it is old and everyone is supposed to have switched to a newer version of Ubuntu. The population of these servers are heavily decreased, so bugs/security issues will not be noticed and/or fixed as easily.
According to https://www.ubuntu.com/pricing/infra , that will cost $75 per virtual server, or $225 per physical server. However, I do not know if that is per month, or per year. I also do know if there is a Non Disclosure Agreement (NDA) involved when you receive security patches as an effect of their extended support.
I will try to send Canonical a message to see if I can provide more information regarding this subject, so you guys can know the cost of maintaining the old Ubuntu 14.04 server… I imagine there will be a few special weirdos that have some reason or another to run old stuff.