I've tried below, but doesn't work:
1:start on (net-device-up IFACE!=lo and runlevel [2345])
2:start on started network-interface INTERFACE=eth1
I saw the networking service is still be brought up by calling these init.d scripts, so I doubt on RHEL 6, there is real a "event" from upstart for NIC's up.
anyone has any idea?