[root@freebsd0:~] ifconfig bce0 alias 172.16.1.81 netmask 255.255.255.0 [root@freebsd0:~] ifconfig bce0 bce0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500 options=c01bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,VLAN_HWTSO,LINKSTATE> ether 00:22:19:5f:52:0b inet 172.16.1.27 netmask 0xffffff00 broadcast 172.16.1.255 inet 172.16.1.81 netmask 0xffffff00 broadcast 172.16.1.255 media: Ethernet autoselect (100baseTX <full-duplex>) status: active vim /etc/rc.conf ifconfig_bce0_alias0="inet 172.16.1.81 netmask 255.255.255.0"