[root@c12 network-scripts]# ifdown eth3 [root@c12 network-scripts]# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.1.0 * 255.255.255.0 U 0 0 0 eth0 192.168.0.0 * 255.255.255.0 U 0 0 0 eth1 192.168.42.0 * 255.255.254.0 U 0 0 0 eth1 [root@c12 network-scripts]# ifup eth3 [root@c12 network-scripts]# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.1.0 * 255.255.255.0 U 0 0 0 eth0 192.168.0.0 * 255.255.255.0 U 0 0 0 eth1 192.168.42.0 * 255.255.254.0 U 0 0 0 eth1 217.112.242.0 * 255.255.254.0 U 0 0 0 eth3 169.254.0.0 * 255.255.0.0 U 0 0 0 eth3 default 217.112.242.1 0.0.0.0 UG 0 0 0 eth3 [root@c12 network-scripts]# ping 217.112.242.1 PING 217.112.242.1 (217.112.242.1) 56(84) bytes of data. From 217.112.242.172 icmp_seq=1 Destination Host Unreachable From 217.112.242.172 icmp_seq=4 Destination Host Unreachable From 217.112.242.172 icmp_seq=6 Destination Host Unreachable From 217.112.242.172 icmp_seq=7 Destination Host Unreachable --- 217.112.242.1 ping statistics --- 9 packets transmitted, 0 received, +4 errors, 100% packet loss, time 8013ms , pipe 3 [root@c12 network-scripts]# ifconfig eth3 eth3 Link encap:Ethernet HWaddr 00:60:08:58:B2:2B inet addr:217.112.242.172 Bcast:217.112.243.255 Mask:255.255.254.0 inet6 addr: fe80::260:8ff:fe58:b22b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:497 errors:0 dropped:0 overruns:0 frame:0 TX packets:954 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:58447 (57.0 KiB) TX bytes:76161 (74.3 KiB) Interrupt:7 Base address:0xb000