A useful ifconfig option is -a, which provides information on all interfaces on your network.
This command produces, for example:
le0: flags=49<UP,LOOPBACK,RUNNING> mtu 8232 inet 127.144.44.140 netmask ff000000 le0:flags=863<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 129.144.44.140 netmask ffffff00 broadcast 129.144.44.255 ether 8:0:20:8:el:fd |
Output that indicates an interface is not running might mean a problem with that interface. In this instance, see the ifconfig(1M) man page.