root@sheep:~# ifconfig eth0 Link encap:Ethernet HWaddr 00:01:02:F1:83:37 inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) Interrupt:11 Base address:0x1000 eth0:0 Link encap:Ethernet HWaddr 00:01:02:F1:83:37 inet addr:192.168.1.20 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:11 Base address:0x1000 eth0:1 Link encap:Ethernet HWaddr 00:01:02:F1:83:37 inet addr:192.168.1.21 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:11 Base address:0x1000 eth0:2 Link encap:Ethernet HWaddr 00:01:02:F1:83:37 inet addr:192.168.1.22 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:11 Base address:0x1000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:5 errors:0 dropped:0 overruns:0 frame:0 TX packets:5 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:448 (448.0 b) TX bytes:448 (448.0 b) root@sheep:~# cat /proc/net/route Iface Destination Gateway Flags RefCnt Use Metric Mask MTU Window IRTT root@sheep:~# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface root@sheep:~# ping 127.0.0.1 PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data. 64 bytes from 127.0.0.1: icmp_seq=1 ttl=0 time=0.309 ms --- 127.0.0.1 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.309/0.309/0.309/0.000 ms root@sheep:~# ping 192.168.1.10 PING 192.168.1.10 (192.168.1.10) 56(84) bytes of data. 64 bytes from 192.168.1.10: icmp_seq=1 ttl=0 time=0.259 ms 64 bytes from 192.168.1.10: icmp_seq=2 ttl=0 time=0.144 ms --- 192.168.1.10 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 999ms rtt min/avg/max/mdev = 0.144/0.201/0.259/0.059 ms root@sheep:~# ping 192.168.1.11 PING 192.168.1.11 (192.168.1.11) 56(84) bytes of data. --- 192.168.1.11 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1016ms root@sheep:~# route del -net 192.168.1.0 netmask 255.255.255.0 eth0 root@sheep:~# route del -net 192.168.1.0 netmask 255.255.255.0 eth0 SIOCDELRT: No such process root@sheep:~# route add -net 192.168.1.0 netmask 255.255.255.0 eth0 root@sheep:~# cat /proc/net/route Iface Destination Gateway Flags RefCnt Use Metric Mask MTU Window IRTT root@sheep:~# ping 192.168.1.11 PING 192.168.1.11 (192.168.1.11) 56(84) bytes of data. --- 192.168.1.11 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1012ms