cis82-E2-7-RIPv2

Chapter 7RIP version 2

CIS 82 Routing Protocols and Concepts

Rick Graziani

Cabrillo College

[email protected]

Spring 2010

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Note My web site is www.cabrillo.edu/~rgraziani. For access to these PowerPoint presentations and other

materials, please email me at [email protected].

Additional information can be found in the Notes section of this presentation.

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For further information This presentation is an

overview of what is covered in the curriculum/book.

For further explanation and details, please read the chapter/curriculum.

Book: Routing Protocols

and Concepts By Rick Graziani and

Allan Johnson ISBN: 1-58713-206-0 ISBN-13: 978-58713-

206-3

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Topics RIPv1 Limitations

RIPv1: Topology Limitations RIPv1: Discontiguous

Networks RIPv1: No VLSM Support RIPv1: No CIDR Support

Configuring RIPv2 Enabling and Verifying RIPv2 Auto-Summary and RIPv2 Disabling Auto-Summary in

RIPv2 Verifying RIPv2 Updates

VLSM and CIDR RIPv2 and VLSM RIPv2 and CIDR

Verifying and Troubleshooting RIPv2 Verification and

Troubleshooting Commands Common RIPv2 Issues Authentication

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Download

Download: cis82-RIPv2-A-student.pkt

To do all configurations in this presentation cis82-RIPv2-A-completed.pkt

Interfaces and RIPv1 already configured Configuration begins with RIPv2

We will use this file throughout this chapter.

RIPv1 Limitations

RIPv1: Topology Limitations RIPv1: Discontiguous Networks RIPv1: No VLSM Support RIPv1: No CIDR Support

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Note on Classful Routing Protocols, RIPv1 limitations The first part of this presentation discusses the limitations of classful

routing protocols such as RIPv1. RIPv1 is used as an example, so we can see how RIPv2 a classless

routing protocol does not have these same limitations. Classful routing protocols have three major limitations:

Does not support discontiguous networks. Does not support VLSM Does not support CIDR

Instead of just “memorizing” these facts, we will demonstrate and “understand” why a classful routing protocol has these limitations.

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RIPv1: Distance Vector, Classess Routing Protocol

RIP Version 2 (RIPv2) is defined in RFC 1723. Classless routing protocol

Less popular than EIGRP, OSPF and IS-IS. RIPv2 is ideal for explaining the differences between a classful

routing protocol (RIPv1) and a classless routing protocol (RIPv2).

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RIPv1 and RIPv2

RIPv2 enhancements over RIPv1: Next-hop addresses included in the routing updates Multicast addresses in sending updates Authentication option available

Both versions of RIP share the following features and limitations: Use of hold-down and other timers Use of split horizon and split horizon with poison reverse Use of triggered updates Maximum hop count of 15 hops

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In a discontiguous network, a classful major network address, such as 172.30.0.0/16, is separated by one or more other major networks.

Classful routing protocols do not include enough routing information to route properly for discontiguous networks.

RIPv1 Limitations

172.30.0.0/16172.30.0.0/16

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R2: static summary route to the 192.168.0.0/16 network. Redistribution - Inject static route(s) into routing protocol updates.

R2(config)# router rip

R2(config-router)# redistribute static

This summary route will cause problems with RIPv1 because: 192.168.0.0/16 is a supernet (more later)

172.30.0.0/16172.30.0.0/16

R2(config)# ip route 192.168.0.0 255.255.0.0 null0

Summary Route

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R1 and R3 contain: Subnets of the 172.30.0.0/16 network

R3 contains VLSM networks 172.30.200.0/24 subnetted again:

172.30.200.16/28 and 172.30.200.32/28

172.30.0.0/16172.30.0.0/16

VLSM

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R3: 172.30.200.0/24 subnetted again, using the first 4 bits for subnets and the last 4 for hosts.

172.30.200.16/28 and 172.30.200.32/28

VLSM

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Private Addresses and Cisco Example Addresses

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Loopback interface Software-only interface Used to emulate an interface

Ideal for simulating multiple networks attached to the same router.

172.30.0.0/16172.30.0.0/16

Loopback InterfacesR3(config)# interface Loopback0

R3(config-if)# ip address 172.30.110.1 255.255.255.0

R3(config)# interface Loopback1


R3(config)# interface Loopback2


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RIPv1 Configurations

Configure RIPv1 for all three routers. Configure a static summary route for 192.168.0.0/16 to null0 on R2.


R1(config-router)# network 172.30.0.0










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CIDR allows route aggregation. A single high-level route entry with a subnet mask less than the

classful mask can be used to represent many lowerlevel routes. Fewer entries in the routing table.

Summarizes all 256 networks ranging from 192.168.0.0/24 to 192.168.255.0/24.

For Lab purposes: The static summary route 192.168.0.0/16 does not actually exist.

R2(config)# ip route 192.168.0.0 255.255.0.0 Null0

Static Routes and Null Interfaces

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Route Redistribution

Redistribution involves taking the routes from one routing source and sending those routes to another routing source.

Routes can only be redistributed into a dynamic routing protocol. Between Dynamic routing protocol Static routes Directly connected networks

Want R2 to redistribute our static route (192.168.0.0/16) into RIPv1. We will see whether this is indeed happening, and if not, why not.




Is static route being sent via RIPv1 with other RIPv1 routes?

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Verifying and Testing Connectivity

Whenever R2 pings any of the 172.30.0.0 subnets on R1 or R3, only about 50 percent of the pings are successful.

R2# ping 172.30.1.1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.30.1.1, timeout is 2 seconds:

!U!.!

Success rate is 60 percent (3/5), round-trip min/avg/max = 28/29/32 ms

R2# ping 172.30.100.1



!U!.!


R2#

172.30.0.0/16172.30.0.0/16What do you expect will happen?

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R1 is able to ping 10.1.0.1 but is unsuccessful when attempting to ping the 172.30.100.1 interface on R3.

R1# ping 10.1.0.1



!!!!!

Success rate is 100 percent (5/5),round-trip min/avg/max = 28/28/28 ms

R1# ping 172.30.100.1



.....

Success rate is 0 percent (0/5)

R1#

XWhat do you expect will happen?

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R3# ping 10.1.0.1



!!!!!

Success rate is 100 percent (5/5),round-trip min/avg/max = 28/28/28 ms

R3# ping 172.30.1.1



.....

Success rate is 0 percent (0/5)

R3#

What do you expect will happen? X

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RIPv1: Discontiguous Networks

Because the subnet mask is not included in the update, RIPv1 and other classful routing protocols must summarize networks at major network boundaries.

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RIPv1 on both Routers R1 and R3 summarize 172.30.0.0 in routing updates to R2.

RIPv1: Discontiguous Networks

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Examining the Routing Tables

What do you expect to see for R2’s routing table? R2 has two equal-cost routes to the 172.30.0.0/16 network.

R2# show ip route

R 172.30.0.0/16 [120/1] via 209.165.200.230, 00:00:09, Serial0/0/0

[120/1] via 209.165.200.234, 00:00:11, Serial0/0/1

209.165.200.0/30 is subnetted, 2 subnets

C 209.165.200.232 is directly connected, Serial0/0/1



C 10.1.0.0 is directly connected, FastEthernet0/0

S 192.168.0.0/16 is directly connected, Null0

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debug ip rip

Notice that the subnet mask is not included with the network address in the update.

R2# debug ip rip

RIP: received v1 update from 209.165.200.230 on Serial0/0/0

172.30.0.0 in 1 hops


172.30.0.0 in 1 hops

What do you expect to see?

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show ip route

R1 has its own 172.30.0.0 routes: 172.30.2.0/24 172.30.1.0/24.

R1 does not send R2 those subnets.

R1# show ip route


C 172.30.2.0 is directly connected, Loopback0



R 209.165.200.232 [120/1] via 209.165.200.229, 00:00:16,Serial0/0/0


R 10.0.0.0/8 [120/1] via 209.165.200.229, 00:00:16, Serial0/0/0

R1#


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Determining the mask and network address

Receiving an Update: Determining subnet mask for routing table What is the major classful network address of the receiving interface? What is the major classful network address of the network in the routing

update? Are they the same major classful network address?

Yes: Apply subnet mask of the receiving interface for this network address in the routing table.

No: Apply classful subnet mask for this network address in the routing table.

Sending an Update: Determining whether or not to summarize route sent What is the major classful network address of the sending interface? What is the major classful network address of the network in the routing

update? Are they the same major classful network address?

Yes: Send subnet network address No: Send summary address – the classful network address

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Example 1 – Name that subnet mask!

172.16.0.0/1610.0.0.0/8 192.168.1.0/24

.1 .1 .1.2

10.0.0.0

192.168.1.0

Apply /8 classful mask


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Example 2 - – Name that subnet mask!

172.16.0.0/16172.17.0.0/16 192.168.1.0/24

.1 .1 .1.2

172.17.0.0

192.168.1.0



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172.16.0.0/24172.17.1.0/24 10.1.1.0/24

.1 .1 .1.2

172.17.0.0 (summary)

10.0.0.0 (summary)



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172.17.2.0/24172.17.1.0/24 10.1.1.0/24

.1 .1 .1.2

172.17.1.0

10.0.0.0 (summary)

Apply /24 interface mask


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172.17.2.0/24172.17.1.0/24

.1 .1 .1.2

172.17.1.0

172.17.3.0



172.17.3.0/24

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172.16.2.0/24172.17.1.0/24

.1 .1 .1.2

172.17.0.0 (Summary)

172.17.0.0 (Summary)

Apply /16 classful mask (route not used)

Apply /16 classful mask (route not used)

172.17.3.0/24

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How Classful Routing Protocols Determine Subnet Masks

172.30.0.0 172.30.0.0

Apply classful default mask of /16


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10.0.0.0



10.0.0.0

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172.30.2.0

172.30.110.0

172.30.1.0172.30.100.0

172.30.200.16

172.30.200.32

VLSM issues: will discuss next

172.30.0.0

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RIPv1: No VLSM Support

When RIPv1 on R3 sends its 172.30.0.0 subnets out its exit interface FastEthernet 0/0, it will only include those 172.30.0.0 subnets with the same subnet mask as the exit interface.

Added R4 for purposes of this discussion

172.30.100.1/24

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RIPv1: No CIDR Support

We see the static route, let’s see if it is be sent in RIPv1 updates with the other RIPv1 routes…






R2(config-router)# end

R2# show ip route

R 172.30.0.0/16 [120/1] via 209.165.200.230, 00:00:09, Serial0/0/0

[120/1] via 209.165.200.234, 00:00:11, Serial0/0/1







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R1 Routing Table

Notice that R1 is not receiving this 192.168.0.0/16 route in its RIP updates from R2

R1# show ip route





R 209.165.200.232 [120/1] via 209.165.200.229, 00:00:16,Serial0/0/0


R 10.0.0.0/8 [120/1] via 209.165.200.229, 00:00:16, Serial0/0/0


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debug ip rip

R2 is not including the 192.168.0.0/16 route in its RIPv1 updates to either R1 or R3.

R2# debug ip rip


172.30.0.0 in 1 hops


172.30.0.0 in 1 hops

RIP: sending v1 update to 255.255.255.255 via Serial0/0/0 (209.165.200.229)

RIP: build update entries

network 10.0.0.0 metric 1

subnet 209.165.200.232 metric 1



network 10.0.0.0 metric 1

subnet 209.165.200.228 metric 1


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RIPv1: No CIDR Support

The static route 192.168.0.0 has a /16 mask. This is fewer bits than the classful Class C mask of /24. RIPv1 and other classful routing protocols cannot support CIDR

routes that are summarized routes with a smaller subnet mask than the classful mask of the route.

RIPv1 ignores these supernets in the routing table and does not include them in updates to other routers.

This is because the receiving router would only be able to apply the larger /24 classful mask to the update and not the shorter /16 mask.

Note: If the 192.168.0.0 static route were configured with a /24 mask or

greater, this route would be included in the RIP updates. The receiving routers would apply the classful /24 mask to this update.




Configuring RIPv2

Enabling and Verifying RIPv2 Auto-Summary and RIPv2 Disabling Auto-Summary in RIPv2 Verifying RIPv2 Updates

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Download

Download: cis82-RIPv2-A-completed.pkt

Interfaces and RIPv1 already configured Configuration begin here with RIPv2

We will use this file throughout this chapter.

44 RIPv2 allows both CIDR and VLSM to be used in the network.

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Enabling and Verifying RIPv2

Default RIPv1: When configuring RIP Router only sends RIPv1 messages, it can process both RIPv1 and

RIPv2 messages. Ignore the RIPv2 fields in the route entry.

RIPv2 will ignore RIPv1 updates.

R2# show ip protocols

<output omitted>

Default version control: send version 1, receive any version

Interface Send Recv Triggered RIP Key-chain

Serial0/0/0 1 1 2

Serial0/0/1 1 1 2

Automatic network summarization is in effect

<output omitted >

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version 2 command is used to modify RIP to use Version 2. This command should be configured on all routers in the routing

domain.


R1(config-router)# version 2





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Routing Protocol is “rip”

Sending updates every 30 seconds, next due in 1 seconds

Invalid after 180 seconds, hold down 180, flushed after 240

Outgoing update filter list for all interfaces is

Incoming update filter list for all interfaces is

Redistributing: static, rip

Default version control: send version 2, receive version 2


Serial0/0/0 2 2

Serial0/0/1 2 2


<output omitted for brevity>

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Restoring RIP to Version 1

Default behavior of RIPv1 can be restored by using either the (slightly different behaviors in sending and receiving): version 1 command no version command

If done, should be configured on all routers.



!or


R1(config-router)# no version

Don’t do this!

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Auto-Summary and RIPv2

You still see the summarized 172.30.0.0/16 route with the same two equal-cost paths.

R2# show ip route

R 172.30.0.0/16 [120/1] via 209.165.200.230, 00:00:28, Serial0/0/0

[120/1] via 209.165.200.234, 00:00:18, Serial0/0/1








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Routers R1 and R3 still do not include the 172.30.0.0 subnets of the other router.

The only difference so far between RIPv1 and RIPV2 is that R1 and R3 each have a route to 192.168.0.0/16. (CIDR) static route configured on R2 and redistributed by RIP.

R1# show ip route


C 172.30.2.0 is directly connected, Loopback0



R 209.165.200.232 [120/1] via 209.165.200.229, 00:00:04,Serial0/0/0


R 10.0.0.0/8 [120/1] via 209.165.200.229, 00:00:04, Serial0/0/0

R 192.168.0.0/16 [120/1] via 209.165.200.229, 00:00:04, Serial0/0/0


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Notice that RIPv2 is sending both the network address and subnet mask.

Notice that the route sent is the summarized classful network address, 172.30.0.0/16 Not the individual 172.30.1.0/24 and 172.30.2.0/24 subnets.

R1# debug ip rip



172.30.0.0/16 via 0.0.0.0, metric 1, tag 0

<output omitted for brevity>


10.0.0.0/8 via 0.0.0.0 in 1 hops

192.168.0.0/16 via 0.0.0.0 in 1 hops

209.165.200.232/30 via 0.0.0.0 in 1 hops


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By default, RIPv2 automatically summarizes networks at major network boundaries, just like RIPv1.

Both R1 and R3 routers are still summarizing their 172.30.0.0 subnets



<output omitted>



FastEthernet0/0 2 2

FastEthernet0/1 2 2

Serial0/1/0 2 2


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Disabling Auto-summary in RIPv2

To modify the default RIPv2 behavior of automatic summarization, use the no auto-summary command


R2(config-router)# no auto-summary






<output omitted>

Automatic network summarization is not in effect

<output omitted>

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Verifying RIPv2 Updates

The routing table for R2 now contains the individual subnets for 172.30.0.0/16. Notice that a single summary route with two equal-cost paths no longer exists. Each subnet and mask has its own specific entry, along with the exit interface and

next-hop address to reach that subnet.

R2# show ip route

172.30.0.0/16 is variably subnetted, 6 subnets, 2 masks

R 172.30.200.32/28 [120/1] via 209.165.200.234, 00:00:09, Serial0/0/1

R 172.30.200.16/28 [120/1] via 209.165.200.234, 00:00:09, Serial0/0/1

R 172.30.2.0/24 [120/1] via 209.165.200.230, 00:00:03, Serial0/0/0

R 172.30.1.0/24 [120/1] via 209.165.200.230, 00:00:03, Serial0/0/0

R 172.30.100.0/24 [120/1] via 209.165.200.234, 00:00:09, Serial0/0/1

R 172.30.110.0/24 [120/1] via 209.165.200.234, 00:00:09, Serial0/0/1








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Fully converged routing tables.

R1# show ip route


R 172.30.200.32/28 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

R 172.30.200.16/28 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

C 172.30.2.0/24 is directly connected, Loopback0

C 172.30.1.0/24 is directly connected, FastEthernet0/0

R 172.30.100.0/24 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

R 172.30.110.0/24 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0


R 209.165.200.232 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0



R 10.1.0.0 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0

R 192.168.0.0/16 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0

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Fully converged routing tables.

R3# show ip route




R 172.30.2.0/24 [120/2] via 209.165.200.233, 00:00:01, Serial0/0/1

R 172.30.1.0/24 [120/2] via 209.165.200.233, 00:00:01, Serial0/0/1





R 209.165.200.228 [120/1] via 209.165.200.233, 00:00:02, Serial0/0/1


R 10.1.0.0 [120/1] via 209.165.200.233, 00:00:02, Serial0/0/1

R 192.168.0.0/16 [120/1] via 209.165.200.233, 00:00:02, Serial0/0/1

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Verifying RIPv2 UpdatesR2# debug ip rip


172.30.100.0/24 via 0.0.0.0 in 1 hops

172.30.110.0/24 via 0.0.0.0 in 1 hops

172.30.200.16/28 via 0.0.0.0 in 1 hops

172.30.200.32/28 via 0.0.0.0 in 1 hops



10.1.0.0/16 via 0.0.0.0, metric 1, tag 0

172.30.100.0/24 via 0.0.0.0, metric 2, tag 0

172.30.110.0/24 via 0.0.0.0, metric 2, tag 0

172.30.200.16/28 via 0.0.0.0, metric 2, tag 0

172.30.200.32/28 via 0.0.0.0, metric 2, tag 0

192.168.0.0/16 via 0.0.0.0, metric 1, tag 0

209.165.200.232/30 via 0.0.0.0, metric 1, tag 0

Sending and receiving routing updates, which are individual routes with their subnet mask instead of a single summary route with the classful mask.

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Notice also that the updates are sent using the multicast address 224.0.0.9.

RIPv1 sends updates as a broadcast 255.255.255.255. In general multicast updates:

Take up less bandwidth on the network. Require less processing by devices that are not RIP enabled.

R2# debug ip rip


VLSM and CIDR

RIPv2 and VLSM RIPv2 and CIDR

60

RIPv2 and VLSM

R3 nows include all the 172.30.0.0 subnets in its routing updates to R4

Because RIPv2 includes the subnet mask with the network address.

Added R4 for purposes of this discussion

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RIPv2 and VLSM

R3# debug ip rip

RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (172.30.100.1)


10.1.0.0/16 via 0.0.0.0, metric 2, tag 0

172.30.1.0/24 via 0.0.0.0, metric 3, tag 0

172.30.2.0/24 via 0.0.0.0, metric 3, tag 0

172.30.110.0/24 via 0.0.0.0, metric 1, tag 0

172.30.200.16/28 via 0.0.0.0, metric 1, tag 0

172.30.200.32/28 via 0.0.0.0, metric 1, tag 0

192.168.0.0/16 via 0.0.0.0, metric 2, tag 0

209.165.200.228/30 via 0.0.0.0, metric 2, tag 0

209.165.200.232/30 via 0.0.0.0, metric 1, tag 0

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RIPv2 and CIDR

Supernets have masks that are smaller than the classful mask (/16 here, instead of the classful /24).

For the supernet to be included in a routing update, the routing protocol must have the capability of carrying that mask.

In other words, it must be a classless routing protocol, like RIPv2.

R2(config)# ip route 192.168.0.0 255.255.0.0 Null0

63

RIPv2 and CIDR

CIDR supernet is included in the routing update sent by R2. Automatic summarization does not have to be disabled on RIPv2 or any

classless routing protocol for supernets to be included in the updates.

R2# debug ip rip



10.1.0.0/16 via 0.0.0.0, metric 1, tag 0

172.30.100.0/24 via 0.0.0.0, metric 2, tag 0

172.30.110.0/24 via 0.0.0.0, metric 2, tag 0

172.30.200.16/28 via 0.0.0.0, metric 2, tag 0

172.30.200.32/28 via 0.0.0.0, metric 2, tag 0

192.168.0.0/16 via 0.0.0.0, metric 1, tag 0

209.165.200.232/30 via 0.0.0.0, metric 1, tag 0

64

RIPv2 and CIDR

R1# show ip route


R 172.30.200.32/28 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

R 172.30.200.16/28 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0



R 172.30.100.0/24 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

R 172.30.110.0/24 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0


R 209.165.200.232 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0



R 10.1.0.0 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0

R 192.168.0.0/16 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0

Verifying and Troubleshooting RIPv2

Verification and Troubleshooting Commands Common RIPv2 Issues Authentication

66

show ip route Command

First command to use to check for network convergence. Important to look for the routes that you expect to be in the

routing table as well as for those that should not be in the routing table.

R1# show ip route


R 172.30.200.32/28 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

R 172.30.200.16/28 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0



R 172.30.100.0/24 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0

R 172.30.110.0/24 [120/2] via 209.165.200.229, 00:00:01, Serial0/0/0


R 209.165.200.232 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0



R 10.1.0.0 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0

R 192.168.0.0/16 [120/1] via 209.165.200.229, 00:00:02, Serial0/0/0

67

show ip interface brief Command

If a network is missing from the routing table, it is often because an interface is down or incorrectly configured.

The show ip interface brief command quickly verifies the status of all interfaces.

R1# show ip interface brief

Interface IP-Address OK? Method Status Protocol

FastEthernet0/0 172.30.1.1 YES NVRAM up up

FastEthernet0/1 172.30.2.1 YES NVRAM up up

Serial0/0/0 209.165.200.230 YES NVRAM up up

Serial0/0/1 unassigned YES NVRAM down down

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show ip protocols Command

Is RIP is enabled, the version of RIP, the status of automatic summarization, and the networks that were included in the network statements.



Sending updates every 30 seconds, next due in 29 seconds

Invalid after 180 seconds, hold down 180, flushed after 240

Outgoing update filter list for all interfaces is not set

Incoming update filter list for all interfaces is not set

Redistributing: rip



FastEthernet0/0 2 2

FastEthernet0/1 2 2

Serial0/0/0 2 2

Automatic network summarization is not in effect

Maximum path: 4

Routing for Networks:

172.30.0.0

209.165.200.0

Routing Information Sources:

Gateway Distance Last Update

209.165.200.229 120 00:00:18

Distance: (default is 120)

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debug ip rip CommandR2# debug ip rip


172.30.100.0/24 via 0.0.0.0 in 1 hops

172.30.110.0/24 via 0.0.0.0 in 1 hops

172.30.200.16/28 via 0.0.0.0 in 1 hops

172.30.200.32/28 via 0.0.0.0 in 1 hops



10.1.0.0/16 via 0.0.0.0, metric 1, tag 0

172.30.100.0/24 via 0.0.0.0, metric 2, tag 0

172.30.110.0/24 via 0.0.0.0, metric 2, tag 0

172.30.200.16/28 via 0.0.0.0, metric 2, tag 0

172.30.200.32/28 via 0.0.0.0, metric 2, tag 0

192.168.0.0/16 via 0.0.0.0, metric 1, tag 0

209.165.200.232/30 via 0.0.0.0, metric 1, tag 0

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ping CommandR2# ping 172.30.2.1



!!!!!


R2# ping 172.30.100.1



!!!!!


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show running-config CommandR1# show running-config

!

hostname R1

!

interface FastEthernet0/0

ip address 172.30.1.1 255.255.255.0

!

interface FastEthernet0/1

ip address 172.30.2.1 255.255.255.0

!

interface Serial0/0/0

ip address 209.165.200.230 255.255.255.252

clock rate 64000

!

router rip

version 2

network 172.30.0.0

network 209.165.200.0

no auto-summary

!

<some output omitted for brevity>

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Common RIPv2 Issues

Version: Although RIPv1 and RIPv2 can be made compatible with additional

commands beyond the scope of this course, RIPv1 does not support discontiguous subnets, VLSM, or CIDR supernet routes.

network statements: Another source of problems might be incorrectly configured or

missing network statements configured with the network command. Remember, the network command does two things:

1. It enables the routing protocol to send and receive updates on any local interfaces that belong to that network.

2. It includes the configured network in its routing updates to its neighboring routers.

A missing or incorrect network statement will result in missed routing updates and routing updates not being sent or received on an interface.

Automatic summarization: If there is a need or expectation for sending specific subnets and

not just summarized routes, make sure that automatic summarization has been disabled with the no auto-summary command.

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It is good practice to authenticate routing information. RIPv2, EIGRP, OSPF, IS-IS, and Border Gateway Protocol (BGP)

can be configured to encrypt and authenticate routing information. Hides the content of the routing information Routers will only accept routing information from other

routers that have been configured with the same password or authentication information.

Authentication

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Topics RIPv1 Limitations

RIPv1: Topology Limitations RIPv1: Discontiguous

Networks RIPv1: No VLSM Support RIPv1: No CIDR Support

Configuring RIPv2 Enabling and Verifying RIPv2 Auto-Summary and RIPv2 Disabling Auto-Summary in

RIPv2 Verifying RIPv2 Updates

VLSM and CIDR RIPv2 and VLSM RIPv2 and CIDR

Verifying and Troubleshooting RIPv2 Verification and

Troubleshooting Commands Common RIPv2 Issues Authentication

Chapter 7RIP version 2

CIS 82 Routing Protocols and Concepts

Rick Graziani

Cabrillo College

[email protected]

cis82-E2-7-RIPv2

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