Hi, I am working on ea-LPC1788 board on uCLinux platform. I have configured the network using 1> ifconfig eth0 100.101.111.225 netmask 255.255.255.0 up 2> route add default gw 100.101.111.111 eth0 After that I connected to my host pc, which IP is 100.101.111.235, it with ping successfully and host pc can ping the board successfully. Host ip is 100.101.111.235. means: ping 100.101.111.235 is working on board and ping 100.101.111.225 is working on host pc successfully. And also host pc can ping the router i.e. ping 100.101.111.111. 64 bytes from 100.101.111.111: icmp_req=1 ttl=64 time=21.5 ms 64 bytes from 100.101.111.111: icmp_req=2 ttl=64 time=6.05 ms 64 bytes from 100.101.111.111: icmp_req=3 ttl=64 time=6.25 ms But when I have connected board via router, it will not ping router from the board i.e. ping 100.101.111.111, it will not work. After pressing ctrl+C I got. PING 100.101.111.111 (100.101.111.111): 56 data bytes ^C --- 100.101.111.111 ping statistics --- 7 packets transmitted, 0 packets received, 100% packet loss This board cannot connect to any pc via router where as all pc are connected to each other via this router and working properly except this board. I have checked the router table: route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 100.101.111.0 * 255.255.255.0 U 0 0 0 eth0 default 100.101.111.111 0.0.0.0 UG 0 0 0 eth0 It will very grateful if someone can help me!