ifconfig em0 192.168.1.10 netmask 255.255.255.0 up
ifconfig em0 192.168.1.11 netmask 255.255.255.255 alias
route add default 192.168.1.1
defaultrouter="192.168.1.1"
ifconfig_em0="inet 192.168.1.10 netmask 255.255.255.0"
ifconfig_em0_alias0="inet 192.168.1.11 netmask 255.255.255.255"