Yup you can confirm it at the console. Drop to the command line using option 8 at the menu then enter ifconfig.
That will show you which NICs are linked. So if you connect only one port you will be able to see which NIC that is.
For example on this box only the WAN is connected:
[admin@4220.stevew.lan]/root: ifconfig
igb0: flags=1008843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,LOWER_UP> metric 0 mtu 1500
options=4e100bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,VLAN_HWFILTER,RXCSUM_IPV6,TXCSUM_IPV6,HWSTATS,MEXTPG>
ether 00:08:a2:0b:c4:86
inet 172.21.16.214 netmask 0xffffff00 broadcast 172.21.16.255
inet6 fe80::208:a2ff:fe0b:c486%igb0 prefixlen 64 scopeid 0x1
media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
nd6 options=823<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL,STABLEADDR>
igb1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
description: LAN
options=4e100bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,VLAN_HWFILTER,RXCSUM_IPV6,TXCSUM_IPV6,HWSTATS,MEXTPG>
ether 00:08:a2:0b:c4:87
inet 192.168.195.1 netmask 0xffffff00 broadcast 192.168.195.255
inet6 fe80::208:a2ff:fe0b:c487%igb1 prefixlen 64 scopeid 0x2
media: Ethernet autoselect
status: no carrier
nd6 options=821<PERFORMNUD,AUTO_LINKLOCAL,STABLEADDR>