I'm taking care of a CentOS 7 system for a local architect. It's running as a Samba 4 fileserver for Windows and Apple workstations. Friday night I tried a tip from ITSprite.com:
http://www.itsprite.com/centos-7-change-network-interface-name-from/
This describes how to rename the default motherboard Ethernet port from "em1" back to "eth0". It works, but it also breaks Samba. All workstations will lose the ability to browse for network printers and files. I haven't dug into the why, so just beware.
--Doc