Updated the Rock2 to Kernel 4.6-rc2, and the Ethernet problem has been fixed..
Fedora 23 (Twenty Three) Kernel 4.6.0-rc2 on an armv7l (ttyS2) ............. ]# uname -a Linux rgrock2 4.6.0-rc2 #1 SMP Sun Apr 3 21:05:44 EDT 2016 armv7l armv7l armv7l GNU/Linux
Details of Kernel changes from -rc1 are here: http://lkml.iu.edu/hypermail/linux/kernel/1604.0/01298.html
Robert Gadsdon. April 3, 2016.