1. Static Routing Exercise u Unix network interface configuration u Cisco network interface configuration u Static routes u Default route u Testing

2. A C B FE I G D H J RouterPC HUB RouterPC HUB RouterPC HUB Router PC HUB RouterPC HUB Router PC HUB Router PC HUB Router PC HUB Router PC HUB Router PC HUB SWITCH Classroom Layout

3. A C B FE I G D H J SWITCH 213.172.133.96/28 213.172.133.128/28 213.172.133.160/28 213.172.133.192/28 213.172.133.224/28 213.172.133.112/28 213.172.133.144/28 213.172.133.176/28 213.172.133.208/28 213.172.133.240/28 Address Allocation 213.172.133.16/28.17.19.21.23.25.18.20.22.24.26

4. Address Allocation u You already have an IP address for your router’s backbone link (A=.17, B=.18, …) u You have a /28 for your local network (PC and router connected to hub) u Allocate your own host addresses from your local /28 network

5. Network interface configuration - FreeBSD u configure interface on Unix host ifconfig fxp0 inet n.n.n.n netmask m.m.m.m –fxp0 is interface name –n.n.n.n is IP address –m.m.m.m is netmask

6. Connect PC to router console u Connect cable to console port on router, serial port on FreeBSD box u Use the tip command to connect your keyboard and screen to the serial port u You may have to edit /etc/remote u See man pages for tip(1) and remote(5)

7. Network interface configuration - Cisco u configure backbone interface on cisco router conf t interface ethernet0/0 ip address n.n.n.n m.m.m.m –ethernet0/0 is interface name –n.n.n.n is IP address –m.m.m.m is netmask u configure local interface on cisco router –ethernet0/1

8. Network interface configuration - Cisco u Cisco global config should always include: ip classless ip subnet-zero u Cisco interface config should usually include: no shutdown no ip proxy-arp no ip redirects

9. Test connectivity u PC can ping local interface of router u Router can ping PC u PC cannot ping backbone interface of router u Router can ping other routers u PC cannot ping other routers or other PCs

10. Add default route u Add route on PC route add default g.g.g.g –g.g.g.g is IP address of gateway (which is on cisco router) u Display forwarding table netstat -f inet -rn

11. Test connectivity u All PCs can now reach backbone IP address of own row u Still can’t reach other rows –why?

12. Add static routes to other rows u On router, add static routes to other rows –next hop is backbone interface of other row’s router ip route n.n.n.n m.m.m.m g.g.g.g u Repeat many times

13. Test connectivity u All routers can reach all PCs u All PCs can reach all backbone IP addresses u All PCs can reach PCs in other rows u Test with traceroute

14. Edit FreeBSD /etc/rc.conf u Don’t do this on classroom machines u On production machines, add lines to /etc/rc.conf to configure network on reboot hostname="porcupine.tomato.example" ifconfig_fxp0="inet 192.0.2.5 netmask 255.255.255.224" defaultrouter="192.0.2.1" u See /etc/default/rc.conf for more information