configuration. Lab Activity Lab Exercise: Converting RIP v1 to RIP v2 In this lab, the students will configure RIP v1 on the routers and then convert to RIP v2. Lab Activity e-Lab Activity: Converting RIP v1 to RIP v2 In this lab, the student will configure RIP v1 and then convert to RIP v2.
Content 1.2 RIP Version 2 1.2.5 Verifying RIP v2 The show ip protocols and show ip route commands display information about routing protocols and the routing table. This section describes how to use show commands to verify the RIP configuration. The show ip protocols command displays values about routing protocols and routing protocol timer information associated with the router. In the example, the router is configured with RIP and sends updated routing table information every 30 seconds. This interval is configurable. If a router running RIP does not receive an update from another router for 180 seconds or more, the first router marks the routes served by the non-updating router as being invalid. In Figure , the holddown timer is set to 180 seconds. Therefore, an update to a route that was down and is now up could stay in the holddown state until the full 180 seconds have passed. If there is still no update after 240 seconds the router removes the routing table entries. In the figure, it has been 18 seconds since Router A received an update from Router B. The router is injecting routes for the networks listed following the Routing for Networks line. The router is receiving routes from the neighboring RIP routers listed following the Routing Information Sources line. The distance default of 120 refers to the administrative distance for a RIP route. The show ip interface brief command can also be used to list a summary of the information and status of an interface. The show ip route command displays the contents of the IP routing table. The routing table contains entries for all known networks and subnetworks, and contains a code that indicates how that information was learned. The output of key fields from this command and their function is explained in the table. Examine the output to see if the routing table is populated with routing information. If entries are missing, routing information is not being exchanged. Use the show running-config or show ip protocols privileged EXEC commands on the router to check for a possible misconfigured routing protocol. Lab Activity Lab Exercise: Verifying RIP v2 Configuration In this lab, the students will configure RIP v1 and v2 on routers and use show commands to verify RIP v2 operation.
Content 1.2 RIP Version 2 1.2.6 Troubleshooting RIP v2 This section explains the use of the debug ip rip command.Use the debug ip rip command to display RIP routing updates as they are sent and received. The no debug all or undebug all commands will turn off all debugging. The example shows that the router being debugged has received updates from one router at source address 10.1.1.2. The router at source address 10.1.1.2 sent information about two destinations in the routing table update. The router being debugged also sent updates, in both cases to broadcast address 255.255.255.255 as the destination. The number in parentheses is the source address encapsulated into the IP header. Other outputs sometimes seen from the debug ip rip command includes entries such as the following: RIP: broadcasting general request on Ethernet0
RIP: broadcasting general request on Ethernet1 These outputs appear at startup or when an event occurs such as an interface transition or a user manually clears the routing table. An entry, such as the following, is most likely caused by a malformed packet from the transmitter: RIP: bad version 128 from 160.89.80.43 Examples of debug ip rip outputs and meanings are shown in Figure . Lab Activity Lab Exercise: Troubleshooting RIP v2 using Debug In this lab, the students will use debug commands to verify proper RIP operation and analyze data transmitted between routers. Lab Activity e-Lab Activity: RIP v2 using Debug In this lab, the students will enable routing on the router, save the configuration, and ping interfaces on routers.
Content 1.2 RIP Version 2 1.2.7 Default routes By default, routers learn paths to destinations three different ways: In Figure , the default route is indicated by the following command: Router(config)#ip route 172.16.1.0 255.255.255.0 172.16.2.1 The ip default-network command establishes a default route in networks using dynamic routing protocols: Router(config)#ip default-network 192.168.20.0 Generally after the routing table has been set to handle all the networks that must be configured, it is often useful to ensure that all other packets go to a specific location. One example is a router that connects to the Internet. This is called the default route for the router. All the packets that are not defined in the routing table will go to the nominated interface of the default router. The ip default-network command is usually configured on the routers that connect to a router with a static default route. In Figure , Hong Kong 2 and Hong Kong 3 would use Hong Kong 4 as the default gateway. Hong Kong 4 would use interface 192.168.19.2 as its default gateway. Hong Kong 1 would route packets to the Internet for all internal hosts. To allow Hong Kong 1 to route these packets it is necessary to configure a default route as: HongKong1(config)#ip route 0.0.0.0 0.0.0.0 192.168.20.1 The zeros represent any destination network with any mask. Default routes are referred to as quad zero routes. In the diagram, the only way Hong Kong 1 can go to the Internet is through the interface 192.168.20.1.
Content Summary An understanding of the following key points should have been achieved: