Cisco Router Config Commands
These commands will configure a router, and make it work with other routers on the internetwork.
configure - terminal: this command puts you in the mode to modify the router either to create a new configuration or to modify an existing one.
Interface: when you configure your router, you are configuring an interface - the port that has the network cable to the internet. A router will have an ethernet interface or a serial interface. Ethernet is for LANs and Serial is for WAN's
example: interface s0
ip address: you have to add an ip address and subnet mask; this identifies the router on the network.
Example: ip address 22.214.171.124 255.255.255.224
router: All routers have their own ip address to identify the nework they are working with. But how does a router know about foreign routers? It has to use a routing protocol, and there are several, such as RIP (Routing Internet Protocol), or EIGRP, (Enhanced Interior Gateway Routing Protocol - a Cisco Specific protocol), or OSPF (Open Shortest Path First). These routing protocols will setup the connection to multiple networks. The router advertises itself to the network and each router builds a routing table with information coming from the other routers. That way each router knows what other router is in its network.
Example: router rip network 10.0.0.0 255.0.0.0 (network identifies the basic network that the router is on.)
ip route: Another way to get to another router is to tell the router how to get to the next router, this is called a static route and it lets the router hook up to another router easily.
example: ip route 126.96.36.199 255.255.255.0 188.8.131.52
Here is a complete example of a command line configuration
- Router#configure terminal Enter configuration commands, one per line. End with CNTL/Z.
- Router(config)#interface serial 3/0
- Router(config-if)#ip address 172.16.55.1 255.255.255.0
- Router(config-if)#bandwidth 256
- Router(config-if)#clock rate 56000
- Router(config-if)#router rip
- Router(config-if)#network 172.16.0.0
- Router(config-if)#no shutdown
- Router(config)#ip route 184.108.40.206 255.255.255.0 220.127.116.11