This post is closely related to RDO Juno Multi Node deployment via packstack on Fedora 21 landscape with boxes having different boards and different Ethernet NICs integrated on boards either plugged into systems.
Originally tested on Two Node Controller&&Network and Compute Fedora 21 . Interfaces on first board (enp3s0,enp5s0) on second board (enp2s0,enp5s1).Converted on both boards to (eth0,eth1), creating udev rules to rename Ethernet interfaces allows to set one to one correspondence between MAC adresses and eth(X) names. Just updating /boot/grub2/grub.cfg is not enough on systems having several NICs.
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