RIPv2RIPv2

Routing Protocols and Concepts – Routing Protocols and Concepts – Chapter 7Chapter 7

By Rajesh Kumar my WayBy Rajesh Kumar my Way

ObjectivesObjectives Encounter and describe the limitations of RIPv1’s Encounter and describe the limitations of RIPv1’s

limitations.limitations. Apply the basic Routing Information Protocol Apply the basic Routing Information Protocol

Version 2 (RIPv2) configuration commands and Version 2 (RIPv2) configuration commands and evaluate RIPv2 classless routing updates.evaluate RIPv2 classless routing updates.

Analyze router output to see RIPv2 support for Analyze router output to see RIPv2 support for VLSM and CIDR. VLSM and CIDR.

Identify RIPv2 verification commands and Identify RIPv2 verification commands and common RIPv2 issues.common RIPv2 issues.

Configure, verify, and troubleshoot RIPv2 in Configure, verify, and troubleshoot RIPv2 in “hands-on” labs.“hands-on” labs.

IntroductionIntroduction Chapter focusChapter focus

Difference between RIPv1 & RIPv2Difference between RIPv1 & RIPv2• RIPv1RIPv1

A classful distance vector routing protocolA classful distance vector routing protocol Does not support discontiguous subnetsDoes not support discontiguous subnets Does not support VLSMDoes not support VLSM Does not send subnet mask in routing updateDoes not send subnet mask in routing update Routing updates are broadcastRouting updates are broadcast

• RIPv2RIPv2 A classless distance vector routing protocol that is an A classless distance vector routing protocol that is an

enhancement of RIPv1’s featuresenhancement of RIPv1’s features Next hop address is included in updatesNext hop address is included in updates Routing updates are multicastRouting updates are multicast The use of authentication is an optionThe use of authentication is an option

Introduction Introduction Similarities between RIPv1 & RIPv2Similarities between RIPv1 & RIPv2

Use of timers to prevent routing loopsUse of timers to prevent routing loops Use of split horizon or split horizon with Use of split horizon or split horizon with

poison reversepoison reverse Use of triggered updatesUse of triggered updates Maximum hop count of 15Maximum hop count of 15

RIPv1 LimitationsRIPv1 Limitations Lab TopologyLab Topology Scenario:Scenario:

3 router set up3 router set up Topology is discontiguousTopology is discontiguous There exists a static summary There exists a static summary

routeroute Static route information can be Static route information can be

injected into routing table injected into routing table updates using redistributionupdates using redistribution

Routers 1 & 3 contain Routers 1 & 3 contain VLSM networks VLSM networks

RIPv1 LimitationsRIPv1 Limitations Scenario ContinuedScenario Continued VLSMVLSM

Recall this is sub Recall this is sub netting the subnetnetting the subnet

Private IP addresses are Private IP addresses are on LAN linkson LAN links

Public IP addresses are Public IP addresses are used on WAN linksused on WAN links

Loopback interfaces Loopback interfaces These are virtual These are virtual interfaces that can be interfaces that can be pinged and added to pinged and added to routing tablerouting table

RIPv1 LimitationsRIPv1 Limitations Null InterfacesNull Interfaces

This is a virtual interface that does not need This is a virtual interface that does not need to be to be created or configuredcreated or configured

Traffic sent to a null interface is discardedTraffic sent to a null interface is discarded Null interfaces do not send or receive traffic Null interfaces do not send or receive traffic

Static routes and null interfacesStatic routes and null interfaces Null interfaces will serve as the exit Null interfaces will serve as the exit

interface for static route interface for static route Example of configuring a static supernet route with a Example of configuring a static supernet route with a

null interfacenull interface R2(config)#ip route 192.168.0.0 255.255.0.0 Null0R2(config)#ip route 192.168.0.0 255.255.0.0 Null0

RIPv1 LimitationsRIPv1 Limitations Route redistributionRoute redistribution

Redistribution command is way to Redistribution command is way to disseminate a disseminate a static route from one static route from one router to another via a routing router to another via a routing protocolprotocol

ExampleExample R2(config-router)#redistribute staticR2(config-router)#redistribute static

RIPv1 LimitationsRIPv1 Limitations Verifying and Testing ConnectivityVerifying and Testing Connectivity

Use the following commands:Use the following commands:• show ip interfaces briefshow ip interfaces brief• pingping• traceroutetraceroute

RIPv1 LimitationsRIPv1 Limitations RIPv1 – RIPv1 – a classful routing protocola classful routing protocol

Subnet mask Subnet mask are not sentare not sent in updates in updates Summarizes networks at major network Summarizes networks at major network

boundariesboundaries If network is discontiguous and RIPv1 If network is discontiguous and RIPv1

configured convergence will not be reachedconfigured convergence will not be reached

RIPv1 LimitationsRIPv1 Limitations Examining the routing Examining the routing

tablestables To examine the To examine the

contents of routing contents of routing updates use the updates use the debug debug ip ripip rip command command

If RIPv1 is If RIPv1 is configured then configured then Subnet masks will not Subnet masks will not be included with the be included with the network addressnetwork address

RIPv1 LimitationsRIPv1 Limitations RIPv1 does not support RIPv1 does not support

VLSMVLSM Reason: RIPv1 does Reason: RIPv1 does

not send subnet mask not send subnet mask in routing updatesin routing updates

RIPv1 does summarize RIPv1 does summarize routes to the Classful routes to the Classful boundary boundary OrOr uses the Subnet uses the Subnet

mask of the outgoing mask of the outgoing interface to determine interface to determine which subnets to which subnets to advertiseadvertise

RIPv1 LimitationsRIPv1 Limitations No CIDR SupportNo CIDR Support In the diagram R2 will In the diagram R2 will

not include the static not include the static route in its update route in its update Reason: Classful Reason: Classful

routing protocols routing protocols do do not support CIDR not support CIDR routes that are routes that are summarized with a summarized with a smaller mask than smaller mask than the classful subnet the classful subnet maskmask

Configuring RIPv2Configuring RIPv2 Comparing RIPv1 & RIPv2 Message Comparing RIPv1 & RIPv2 Message

FormatsFormats RIPv2 Message format is RIPv2 Message format is similarsimilar to RIPv1 to RIPv1 butbut

has 2 extensionshas 2 extensions• 1st extension is the subnet mask field1st extension is the subnet mask field• 2nd extension is the addition of next hop address2nd extension is the addition of next hop address

Configuring RIPv2Configuring RIPv2 Enabling and Verifying RIPv2Enabling and Verifying RIPv2 Configuring RIP on a Cisco routerConfiguring RIP on a Cisco router

By By defaultdefault it is running it is running RIPv1RIPv1

Configuring RIPv2Configuring RIPv2 Configuring Configuring RIPv2RIPv2

on a Cisco routeron a Cisco router Requires using the Requires using the

version 2version 2 command command RIPv2 ignores RIPv2 ignores

RIPv1 updatesRIPv1 updates To verify RIPv2 is To verify RIPv2 is

configured use theconfigured use the show ip protocolsshow ip protocols

command command

Configuring RIPv2Configuring RIPv2 Auto-Summary & Auto-Summary &

RIPv2RIPv2 RIPv2 will RIPv2 will

automatically automatically summarize routes at summarize routes at major network major network boundaries boundaries andand can can also summarize routes also summarize routes with a subnet mask with a subnet mask that is smaller than the that is smaller than the classful subnet maskclassful subnet mask

Disabling Auto-Disabling Auto-Summary in RIPv2Summary in RIPv2

To disable automatic To disable automatic summarization issue summarization issue the the no auto-summaryno auto-summary commandcommand

Configuring RIPv2Configuring RIPv2

Configuring RIPv2Configuring RIPv2 Verifying RIPv2 UpdatesVerifying RIPv2 Updates When using RIPv2 with automatic When using RIPv2 with automatic

summarization turned offsummarization turned off Each subnet and mask has its own specific Each subnet and mask has its own specific

entry, along with the exit interface and next-entry, along with the exit interface and next-hop address to reach that subnethop address to reach that subnet

To verify information being sent by RIPv2 use To verify information being sent by RIPv2 use thethe debug ip ripdebug ip rip command command

VLSM & CIDRVLSM & CIDR RIPv2 and VLSMRIPv2 and VLSM Networks using a Networks using a

VLSM IP addressing VLSM IP addressing scheme scheme Use Use classless classless

routing protocolsrouting protocols (i.e. RIPv2) to (i.e. RIPv2) to disseminate network disseminate network addresses and their addresses and their subnet maskssubnet masks

VLSM & CIDRVLSM & CIDR CIDR uses SupernettingCIDR uses Supernetting

Supernetting is a bunch of contiguous Supernetting is a bunch of contiguous classful networks that is addressed as a classful networks that is addressed as a single networksingle network

VLSM & CIDRVLSM & CIDR To To verifyverify that that

supernetssupernets are are being sent and being sent and received use the received use the following following commandscommands Show ip routeShow ip route Debug ip ripDebug ip rip

Verifying & Troubleshooting Verifying & Troubleshooting RIPv2RIPv2

Basic TroubleshootingBasic Troubleshooting steps steps Check the status of all linksCheck the status of all links Check cablingCheck cabling Check IP address & subnet mask configurationCheck IP address & subnet mask configuration Remove any unneeded configuration commandsRemove any unneeded configuration commands

Commands used to verify proper operation of RIPv2Commands used to verify proper operation of RIPv2 Show ip interfaces briefShow ip interfaces brief Show ip protocolsShow ip protocols Debug ip ripDebug ip rip Show ip routeShow ip route

Verifying & Troubleshooting Verifying & Troubleshooting RIPv2RIPv2

Common RIPv2 IssuesCommon RIPv2 Issues When trouble shooting RIPv2 examine the following When trouble shooting RIPv2 examine the following

issues:issues: VersionVersion

Check to make sure you are using version 2Check to make sure you are using version 2 Network statementsNetwork statements

Network statements may be incorrectly typed or missingNetwork statements may be incorrectly typed or missing Automatic summarizationAutomatic summarization

If summarized routes are not needed then disable automatic If summarized routes are not needed then disable automatic summarizationsummarization

Verifying & Troubleshooting Verifying & Troubleshooting RIPv2RIPv2

Reasons why it’s good to authenticate routing Reasons why it’s good to authenticate routing information information Prevent the possibility of accepting invalid routing Prevent the possibility of accepting invalid routing

updatesupdates Contents of routing updates are encryptedContents of routing updates are encrypted

Types of routing protocols that can use authenticationTypes of routing protocols that can use authentication RIPv2RIPv2 EIGRPEIGRP OSPFOSPF IS-ISIS-IS BGPBGP

SummarySummary

RoutingRoutingProtocolProtocol

DistancDistancee

VectorVector

ClasslessClasslessRoutingRoutingProtocolProtocol

UsesUsesHold-Hold-DownDownTimersTimers

Use ofUse ofSplit Split

HorizoHorizon orn orSplit Split

HorizoHorizon w/n w/

Poison Poison ReversRevers

ee

MaxMaxHop Hop countcount= 15= 15

AutoAutoSummarSummar

yy

SupporSupportt

CIDRCIDR

SupportSupportss

VLSMVLSM

Uses Uses AutheAuthe

n-n-ticatioticatio

nn

RIPv1RIPv1 YesYes NoNo YesYes YesYes YesYes YesYes NoNo NoNo NoNo

RIPRIPvv22 YesYes YesYes YesYes YesYes YesYes YesYes YesYes YesYes YesYes