In preparation of your CCNA exam, we want to make sure we cover the various concepts that we could see on your Cisco CCNA exam. So to assist you, below we will discuss one of the more difficult CCNA concepts; the Three Router Static Route Lab. As you progress through your CCNA exam studies, I am sure with repetition you will find this topic becomes easier. So even though it may be a difficult concept and confusing at first, keep at it as no one said getting your Cisco certification would be easy!
In this lab, you will configure static routes between all three routers. This will allow your routers to route packets so that all routers and all hosts will be able to reach (ping) each other. Once your configuration is complete, you will use basic techniques to test your network’s connectivity.
Three separate classful networks need routing between them and their subnets.
- What are the different classful networks?
- Are there any subnets? If so, what are they?
- Configure the cabling as shown in the network diagram
- If the routers have a startup-config, erase it and perform a reload of the routers.
- Important! Configure the routers to include hostnames and the proper interface commands including IP addresses, subnet masks, etc. Each router should be able to ping the interface of the adjacent (neighboring) router and the host on its LAN (Ethernet) interface. Test and troubleshoot as necessary. Use the context sensitive help, previous labs, your books and /or handouts and if your still having problems ask your partner or ask the instructor for assistance.
Step 1 – Configuring Static Routes
On each router configure a separate and specific static route for each network or subnet. You do not need to configure static routes for the router’s directly connected network(s) because like a host, by configuring the IP address and subnet mask on an interface tells the router that it belongs to that network/subnet.
- Router1(config)# ip route 172.16.3.0 255.255.255.0 172.16.2.1
- Router1(config)# ip route 192.168.2.0 255.255.255.0 192.168.1.1
- Router2(config)# ip route 172.16.1.0 255.255.255.0 172.16.2.2
- Router2(config)# ip route 192.168.1.0 255.255.255.0 172.16.2.2
- Router2(config)# ip route 192.168.2.0 255.255.255.0 172.16.2.2
- Router3(config)# ip route 172.16.1.0 255.255.255.0 192.168.1.2
- Router3(config)# ip route 172.16.2.0 255.255.255.0 192.168.1.2
- Router3(config)# ip route 172.16.3.0 255.255.255.0 192.168.1.2
Verify and Validate:
- All hosts and all routers should be able to ping every interface in the network.
- Do a show running-config and notice the static routes that you entered.
- Do a show ip route
1) What routes to networks do you see?
2) Which routes are static and which routes are directly connected?
3) What is the administrative distance for a static route?
4) What is the administrative distance for a directly connected network?
- 5) How does the next-hop-ip-address help with the routing process?
- 6) Does it give the entire route, i.e., subnet mask?
- 7) What is it actually doing regarding the routing of the packet?
- 8) How does a packet get from Host 2 to Host 3?
- 9) Instead of a next-hop-ip-address, what else could you have used?
- 10) What would you need to do if you added new networks or deleted/modified existing networks?
- 11) Is there any way to summarize several static routes to multiple subnets into a single static route?
Router2#show ip route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets