On RHEL6 and RHEL7 once you add a second interface on the same subnet, it does not work ( no ping)
The cause of the problem is a change on the parameter rp_filter
vi /etc/sysctl.conf
net.ipv4.conf.default.rp_filter = 2
net.ipv4.conf.all.rp_filter = 2
sysctl -p
ref
https://access.redhat.com/solutions/53031