1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000
    link/ether 6c:f0:49:0d:92:c5 brd ff:ff:ff:ff:ff:ff
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000
    link/ether c8:3a:35:d9:04:68 brd ff:ff:ff:ff:ff:ff
    inet 10.1.20.15/22 brd 10.1.23.255 scope global eth1
    inet6 fe80::ca3a:35ff:fed9:468/64 scope link 
       valid_lft forever preferred_lft forever
4: vboxnet0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether 0a:00:27:00:00:00 brd ff:ff:ff:ff:ff:ff
5: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1416 qdisc pfifo_fast state UNKNOWN qlen 3
    link/ppp 
    inet 172.16.20.15 peer 172.16.21.254/32 scope global ppp0