determining ip routes

8/14/2019 Determining Ip Routes

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1999, Cisco Systems, Inc. 9-1

Chapter 9

Determining IPRoutes


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1999, Cisco Systems, Inc. www.cisco.com ICND9-2

Objectives

Upon completion of this chapter, you willbe able to complete the following tasks:

Distinguish the use and operation of static and

dynamic routes

Configure and verify a static route

Identify how distance vector IP routing protocolssuch as RIP and IGRP operate on Cisco routers

Enable Routing Information Protocol (RIP)

Enable Interior Gateway Routing Protocol (IGRP)

Verify IP routing with show and debug commands


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To route a router need to know:

Destination addresses

Sources it can learn from

Possible routes

Best route

Maintain and verify routing information

What is Routing?

172.16.1.010.120.2.0


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What is Routing? (cont.)

NetworkProtocol

DestinationNetwork

ConnectedLearned

10.120.2.0172.16.1.0

ExitInterface

E0S0

Routed Protocol: IP

Routers must learn destinations that are not

directly connected

172.16.1.010.120.2.0

E0S0


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Static Route

Uses a route that anetworkadministrator entersinto the router

manually

Dynamic Route

Uses a route that anetwork routingprotocol adjustsautomatically for

topology or trafficchanges

Identifying Static and DynamicRoutes


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172.16.2.1

SO

Static Routes

172.16.1.0

B172.16.2.2

NetworkA

Configure unidirectional static routes to and from a stubnetwork to allow communications to occur.

B

Stub Network


7/701999, Cisco Systems, Inc. www.cisco.com ICND9-7

Defines a path to an IP destination network or subnet

Router(config)#ip route network [mask]

{address | interface}[distance] [permanent]

Static Route Configuration



Stub Network

ip route 172.16.1.0 255.255.255.0 172.16.2.1

172.16.2.1

SO

Static Route Example

172.16.1.0

B172.16.2.2

NetworkA B

This is a unidirectional route. You must have a route configured in

the opposite direction.



Stub Network

ip route 0.0.0.0 0.0.0.0 172.16.2.2

Default Routes

172.16.2.1

SO

172.16.1.0

B172.16.2.2

NetworkA B

This route allows the stub network to reach all known networks

beyond router A.



What is a Routing Protocol?

Routing protocols are

used betweenrouters to determinepaths and maintainrouting tables.

Once the path isdetermined a router canroute a routed protocol.

NetworkProtocol

DestinationNetwork

ConnectedRIP

IGRP

10.120.2.0172.16.2.0172.17.3.0

ExitInterface

E0S0S1

Routed Protocol: IPRouting protocol: RIP, IGRP

172.17.3.0

172.16.1.010.120.2.0

E0S0



Autonomous System 100 Autonomous System 200

IGPs: RIP, IGRP EGPs: BGP

Autonomous Systems: Interior orExterior Routing Protocols

An autonomous system is a collection of networksunder a common administrative domain

IGPs operate within an autonomous system

EGPs connect different autonomous systems



Administrative Distance:Ranking Routes

IGRPAdministrativeDistance=100

Router DRouter D

Router BRouter BRouter ARouter A

Router CRouter C

RIPAdministrativeDistance=120

EE

I need to send a packet to

Network E. Both router B

and C will get it there.

Which route is best?



Classes of Routing Protocols

Distance Vector

Hybrid Routing

Link StateCC

BB

AA

DD

CC

DD

BB

AA



Distance Vector RoutingProtocols

Pass periodic copies of routing table to neighborrouters and accumulate distance vectors

CC

DD

BB

AA

CC BB AADD

RoutingTable

RoutingTable

RoutingTable

RoutingTable

DistanceHow farVectorIn which direction



Routers discover the best path todestinations from each neighbor

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0

Routing Table

10.2.0.0

10.3.0.0

0

0

S0

S1

Routing Table

10.3.0.0 S0 0

10.4.0.0 E0 0

Routing Table

10.1.0.0

10.2.0.0

E0

S0

0

0

Distance VectorSources ofInformation and Discovering Routes




AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0

Routing Table

10.1.0.0

10.2.0.0

10.3.0.0

Routing Table

10.2.0.0

10.3.0.0

10.4.0.0

10.1.0.0

0

0

1

1

S0

S1

S1

S0

Routing Table

10.3.0.0 S0 0

10.4.0.0 E0 0

10.2.0.0 S0

1

E0

S0

S0 1

0

0






AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0

Routing Table

10.1.0.0

10.2.0.0

10.3.0.0

10.4.0.0

Routing Table

10.2.0.0

10.3.0.0

10.4.0.0

10.1.0.0

0

0

1

1

S0

S1

S1

S0

Routing Table

10.3.0.0 S0 0

10.4.0.0 E0 0

10.2.0.0 S0

10.1.0.0 S0

1

2

E0

S0

S0

S0

1

2

0

0



Distance VectorSelectingBest Route with Metrics

Information used to select the best path for routing

56T1

56

T1Ticks, hop count

B

A

Hop count

IPX

RIP

IGRP

Bandwidth

Delay

Load

Reliability

MTU



Do not delete



Distance VectorMaintainingRouting Information

Updates proceed step-by-stepfrom router to router

AA

Process toupdate this

routingtable

TopologyTopologychangechange

causescauses

routingrouting

tabletable

updateupdate





AA


routingtable

Router A sendsout this updated

routing tableafter the

next periodexpires

Topologychangecausesrouting

tableupdate





AABB


routingtable


routingtable

Topologychangecausesrouting

tableupdate

Router A sendsout this updatedrouting table

after thenext period

expires


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Maintaining Routing InformationProblemRouting Loops

Each node maintains the distance from itself to eachpossible destination network

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0

Routing Table

10.3.0.0 S0

E0

S0

S0

1

210.1.0.0

10.2.0.0

10.4.0.0

0

0

Routing Table

10.1.0.0 E0

S0

S0

S0

1

210.4.0.0

10.3.0.0

10.2.0.0

0

0

Routing Table

10.2.0.0 S0

S1

S1

S0

1

110.1.0.0

10.4.0.0

10.3.0.0

0

0


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Slow convergence produces inconsistent routing

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0 XX

Routing Table

1

2

Routing Table

1

2

Routing Table

1

1


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Router C concludes that the best path to network10.4.0.0 is through Router B


AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0


Routing Table

1

2

Routing Table

1

2

Routing Table

1

1


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Router A updates its table to reflect the new buterroneous hop count


AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0


Routing Table

1

2

Routing Table

1

4

Routing Table

3

1


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Symptom: Counting to Infinity

Packets for network 10.4.0.0 bounce between routersA, B, and C

Hop count for network 10.4.0.0 counts to infinity

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0


Routing Table

1

2

Routing Table

1

6

Routing Table

5

1


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Solution: Defining a Maximum

Define a limit on the number of hops to preventinfinite loops

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0


Routing Table

10.3.0.0 S0

S0

S0

S0

1

210.1.0.0

10.2.0.0

10.4.0.0

0

16

Routing Table

E0

S0

S0

S0

1

16

10.1.0.0

10.4.0.0

10.3.0.0

10.2.0.0

0

0

Routing Table

S0

S1

S1

S0

16

1

10.2.0.0

10.1.0.0

10.4.0.0

10.3.0.0

0

0


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Solution: Split Horizon

It is never useful to send information about a route backin the direction from which the original packet came

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0 XXXXXX

Routing Table

1

2

Routing Table

1

2

Routing Table

1

2


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Solution: Route Poisoning

Routers set the distance of routes that have gone downto infinity

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0


Routing Table

10.3.0.0 S0

S0

S0

S0

1

210.1.0.0

10.2.0.0

10.4.0.0

0

Infinity

Routing Table

10.1.0.0 E0

S0

S0

S0

1

210.4.0.0

10.3.0.0

10.2.0.0

0

0

Routing Table

10.2.0.0 S0

S1

S1

E1

1

210.1.0.0

10.4.0.0

10.3.0.0

0

0


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Solution: Poison Reverse

Poison Reverse overrides split horizon

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0


Routing Table

10.3.0.0 S0

S0

S0

S0

1

210.1.0.0

10.2.0.0

10.4.0.0

0

Infinity

Routing Table

10.1.0.0 E0

S0

S0

S0

1

210.4.0.0

10.3.0.0

10.2.0.0

0

0

Routing Table

10.2.0.0 S0

S1

S1

E1

PossiblyDown

210.1.0.0

10.4.0.0

10.3.0.0

0

0

PoisonReverse


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Solution: Hold-Down Timers

Router keeps an entry for the network possibly downstate, allowing time for other routers to recompute for thistopology change

Network 10.4.0.0 is downthen back up

then back down

Update afterhold-down Time

Network 10.4.0.0is unreachable

AA BB CC

10.1.0.0 10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0 XXUpdate after

hold-down Time


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Solution: Triggered Updates

Router sends updates when a change in its routingtable occurs

AA BB CC

10.2.0.0 10.3.0.0 10.4.0.0

E0 S0 S0 S1 S0 E0 X




10.1.0.0


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Blank Slide for Instructor Notes


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Implementing Solutions inMultiple Routes

DD

BBEE

AA

X CC10.4.0.0


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Implementing Solutions inMultiple Routes (cont.)

DD

BBEE

AA

CCX10.4.0.0

Holddown

Holddown

Holddown


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DD

BBEE

AA

CCX10.4.0.0

Holddown

Holddown

Holddown

Poison Reverse

Poison Reverse

Poison Reverse

Poison Reverse

I l i S l i i


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DD

BBEE

AA

CCX10.4.0.0

Holddown

Holddown

Holddown

Packet forNetwork 10.4.0.0

Packet forNetwork 10.4.0.0


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DD

BBEE

AA

CCLink up!Link up!

10.4.0.0

I l i S l i i


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DD

BBEE

AA

CCLink up!

10.4.0.0


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Link-State Routing Protocols

After initial flood, pass small event-triggered link-stateupdates to all other routers

Link-State Packets

SPFAlgorithm

TopologicalDatabase

Shortest Path First Tree

RoutingTable

CC AA

DD

BB


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IP R i


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Router configuration

Select routing protocols

Specify networks orinterfaces

Network160.89.0.0

Network 172.30.0.0

IGRP,RIP

Network 172.16.0.0

RIP

RIP

IGRP

IP RoutingConfiguration Tasks

D i R i


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Defines an IP routing protocol

er(config)#routerprotocol [keyword]

Mandatory configuration command for each

IP routing process

Identifies the physically connected network

that routing updates are forwarded to

(config-router)#network network-number

Dynamic RoutingConfiguration


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19.2 kbps

T1

T1 T1

Hop count metric selects the path

Routes update every 30 seconds

RIP Overview


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Starts the RIP routing process

er(config)#router rip

config-router)#network network-number

Selects participating attached networks The network number must be a major classful

network number

RIP Configuration


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2.3.0.0router rip

network 172.16.0.0

network 10.0.0.0

RIP Configuration Example

router rip

network 10.0.0.0

2.3.0.0router rip

network 192.168.1.0

network 10.0.0.0

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

V if i th R ti P t l


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Verifying the Routing ProtocolRIP

RouterA#sh ip protocolsRouting Protocol is "rip"

Sending updates every 30 seconds, next due in 0 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: rip

Default version control: send version 1, receive any version

Interface Send Recv Key-chain

Ethernet0 1 1 2Serial2 1 1 2

Routing for Networks:

10.0.0.0

172.16.0.0

Routing Information Sources:

Gateway Distance Last Update

10.1.1.2 120 00:00:10

Distance: (default is 120)

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

Di l i th


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Displaying theIP Routing Table

RouterA#sh ip route

Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP

i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate

default

U - per-user static route, o - ODR

T - traffic engineered route

Gateway of last resort is not set

172.16.0.0/24 is subnetted, 1 subnets

C 172.16.1.0 is directly connected, Ethernet0


R 10.2.2.0 [120/1] via 10.1.1.2, 00:00:07, Serial2

C 10.1.1.0 is directly connected, Serial2

R 192.168.1.0/24 [120/2] via 10.1.1.2, 00:00:07, Serial2

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0


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debug ip ripCommand

RouterA#debug ip rip

RIP protocol debugging is on

RouterA#

00:06:24: RIP: received v1 update from 10.1.1.2 on Serial2

00:06:24: 10.2.2.0 in 1 hops

00:06:24: 192.168.1.0 in 2 hops

00:06:33: RIP: sending v1 update to 255.255.255.255 via

Ethernet0 (172.16.1.1)

00:06:34: network 10.0.0.0, metric 100:06:34: network 192.168.1.0, metric 3

00:06:34: RIP: sending v1 update to 255.255.255.255 via

Serial2 (10.1.1.1)

00:06:34: network 172.16.0.0, metric 1

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0


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More scalable than RIP

Sophisticated metric

Multiple-path support

Introduction to IGRP

IGRP


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Bandwidth

Delay

Reliability

Loading

MTU

19.2 kbps19.2 kbps

IGRP Composite Metric

Source

Destination

Blank Slide for Instructor


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Blank Slide for InstructorNotes


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Maximum six paths

Next-hop router closer to destination

Within metric variance

New Route

InitialRoute

Source

Destination

IGRP Unequal Multiple Paths


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Configuring IGRP

config-router)#network network-number

Selects participating attached networks

Router(config)#router igrp autonomous-system

Defines IGRP as the IP routing protocol


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Configuring IGRP (cont.)

er(config-router)#traffic-share

lanced | min }

Control how load-balanced traffic is distributed

Router(config-router)#variancemultiplier

Control IGRP load balancing


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router igrp 100

network 172.16.0.0

network 10.0.0.0

IGRP Configuration Example

router igrp 100

network 10.0.0.0

router igrp 100

network 192.168.1.0

network 10.0.0.0

Autonomous System = 100

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

Verifying the Routing Protocol


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Verifying the Routing ProtocolIGRP

RouterA#sh ip protocols

Routing Protocol is "igrp 100"

Sending updates every 90 seconds, next due in 21 secondsInvalid after 270 seconds, hold down 280, flushed after 630

Outgoing update filter list for all interfaces is

Incoming update filter list for all interfaces is

Default networks flagged in outgoing updates

Default networks accepted from incoming updates

IGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0

IGRP maximum hopcount 100

IGRP maximum metric variance 1

Redistributing: igrp 100

Routing for Networks:

10.0.0.0

172.16.0.0

Routing Information Sources:

Gateway Distance Last Update

10.1.1.2 100 00:01:01

Distance: (default is 100)

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

Displaying the


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Displaying theIP Routing Table

RouterA#sh ip routeCodes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP



E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP

i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default





C 172.16.1.0 is directly connected, Ethernet0


I 10.2.2.0 [100/90956] via 10.1.1.2, 00:00:23, Serial2

C 10.1.1.0 is directly connected, Serial2

I 192.168.1.0/24 [100/91056] via 10.1.1.2, 00:00:23, Serial2

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

debug ip igrp transaction


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debug ip igrp transactionCommand

RouterA#debug ip igrp transactionsIGRP protocol debugging is on

RouterA#

00:21:06: IGRP: sending update to 255.255.255.255 via Ethernet0 (172.16.1.1)

00:21:06: network 10.0.0.0, metric=88956

00:21:06: network 192.168.1.0, metric=91056

00:21:07: IGRP: sending update to 255.255.255.255 via Serial2 (10.1.1.1)

00:21:07: network 172.16.0.0, metric=1100

00:21:16: IGRP: received update from 10.1.1.2 on Serial200:21:16: subnet 10.2.2.0, metric 90956 (neighbor 88956)

00:21:16: network 192.168.1.0, metric 91056 (neighbor 89056)

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

debug ip igrp events


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debug ip igrp eventsCommand

RouterA#debug ip igrp eventsIGRP event debugging is on

RouterA#

00:23:44: IGRP: sending update to 255.255.255.255 via Ethernet0 (172.16.1.1)

00:23:44: IGRP: Update contains 0 interior, 2 system, and 0 exterior routes.

00:23:44: IGRP: Total routes in update: 2




00:23:48: IGRP: received update from 10.1.1.2 on Serial2



172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

Updating Routing Information


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Updating Routing InformationExample

RouterA# debug ip igrp trans

00:31:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to down

00:31:15: IGRP: edition is now 3


00:31:15: network 172.16.0.0, metric=4294967295



00:31:16: IGRP: broadcasting request on Serial2

00:31:16: IGRP: received update from 10.1.1.2 on Serial200:31:16: subnet 10.2.2.0, metric 90956 (neighbor 88956)

00:31:16: network 172.16.0.0, metric 4294967295 (inaccessible)

00:31:16: network 192.168.1.0, metric 91056 (neighbor 89056)



172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0X



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Updating Routing InformationExample (cont.)

RouterB#debug ip igrp trans

IGRP protocol debugging is on

RouterB#

1d19h: IGRP: sending update to 255.255.255.255 via Serial2 (10.1.1.2)1d19h: subnet 10.2.2.0, metric=88956

1d19h: network 192.168.1.0, metric=89056

1d19h: IGRP: sending update to 255.255.255.255 via Serial3 (10.2.2.2)

1d19h: subnet 10.1.1.0, metric=88956


1d19h: IGRP: received update from 10.1.1.1 on Serial2

1d19h: network 172.16.0.0, metric 4294967295 (inaccessible)

1d19h: IGRP: edition is now 10


1d19h: subnet 10.2.2.0, metric=88956




1d19h: subnet 10.1.1.0, metric=88956


172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0



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RouterB#sh ip route

Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP



E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGPi - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default




I 172.16.0.0/16 is possibly down, routing via 10.1.1.1, Serial2


C 10.1.1.0 is directly connected, Serial2C 10.2.2.0 is directly connected, Serial3

I 192.168.1.0/24 [100/89056] via 10.2.2.3, 00:00:14, Serial3

RouterB#ping 172.16.1.1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:

.....

Success rate is 0 percent (0/5)

RouterB#

172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0X



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172.16.1.1

S2E0 S3

192.168.1.110.1.1.1 10.2.2.210.1.1.2

S2 S3

10.2.2.3

172.16.1.0 A B C192.168.1.0

E0

RouterB#debug ip igrp transactionsRouterB#

1d20h: IGRP: received update from 10.1.1.1 on Serial21d20h: network 172.16.0.0, metric 89056 (neighbor 1100)

RouterB#RouterB#sh ip route

Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGPD - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGPi - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default

U - per-user static route, o - ODRT - traffic engineered route


I 172.16.0.0/16 is possibly down, routing via 10.1.1.1, Serial2

10.0.0.0/24 is subnetted, 2 subnetsC 10.1.1.0 is directly connected, Serial2C 10.2.2.0 is directly connected, Serial3I 192.168.1.0/24 [100/89056] via 10.2.2.3, 00:00:18, Serial3

RouterB#ping 172.16.1.1

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 32/38/48 ms


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With ip classless Default

With no ip classless Drop

outer(config)#ip classless

ip classlessCommand

S0

Default route

172.16.0.0

E0

10.1.0.0

NetworkProtocol

DestinationNetwork

CC

RIP

10.1.0.0

10.2.0.0

172.16.0.0 via0.0.0.0

ExitInterface

E0S0

S0E0

10.2.0.0

To get to 10.7.1.1:


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Visual Objective

core_ server

10.1.1.1

wg_sw_a10.2.2.11

wg_sw_l

10.13.13.11

wg_pc_a10.2.2.12

wg_pc_l10.13.13.12

wg_ro_a

10.13.13.3

e0/1 e0/2

e0/2

e0/1

e0

e0

fa0/23

core_sw_a10.1.1.2

10.2.2.3

wg_ro_l

core_ro10.1.1.3

fa0/24 fa0/0

s010.140.1.2/24

s0

10.140.12.2/24

s1/0 - s2/3

10.140.1.1/24 10.140.12.1/24

pod ros s0 ros e0 swA 10.140.1.2 10.2.2.3 10.2.2.11B 10.140.2.2 10.3.3.3 10.3.3.11C 10.140.3.2 10.4.4.3 10.4.4.11D 10.140.4.2 10.5.5.3 10.5.5.11E 10.140.5.2 10.6.6.3 10.6.6.11F 10.140.6.2 10.7.7.3 10.7.7.11G 10.140.7.2 10.8.8.3 10.8.8.11H 10.140.8.2 10.9.9.3 10.9.9.11

I 10.140.9.2 10.10.10.3 10.3.3.11J 10.140.10.2 10.11.11.3 10.11.11.11K 10.140.11.2 10.12.12.3 10.12.12.11L 10.140.12.2 10.13.13.3 10.13.13.11

RIP

RIP

...

LL


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Visual Objective

core_ server

10.1.1.1

wg_sw_a10.2.2.11

wg_sw_l10.13.13.11

wg_pc_a10.2.2.12

wg_pc_l10.13.13.12

wg_ro_a

10.13.13.3

e0/1e0/2

e0/2e0/1

e0

e0

fa0/23

core_sw_a10.1.1.2

10.2.2.3

wg_ro_l

core_ro10.1.1.3

fa0/24 fa0/0

LL

s010.140.1.2/24

s0

10.140.12.2/24

s1/0 - s2/3

10.140.1.1/24 10.140.12.1/24...

pod ros s0 ros e0 swA 10.140.1.2 10.2.2.3 10.2.2.11B 10.140.2.2 10.3.3.3 10.3.3.11C 10.140.3.2 10.4.4.3 10.4.4.11D 10.140.4.2 10.5.5.3 10.5.5.11E 10.140.5.2 10.6.6.3 10.6.6.11F 10.140.6.2 10.7.7.3 10.7.7.11G 10.140.7.2 10.8.8.3 10.8.8.11H 10.140.8.2 10.9.9.3 10.9.9.11

I 10.140.9.2 10.10.10.3 10.3.3.11J 10.140.10.2 10.11.11.3 10.11.11.11K 10.140.11.2 10.12.12.3 10.12.12.11L 10.140.12.2 10.13.13.3 10.13.13.11

IGRP

IGRP


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Summary

After completing this chapter, you should beable to perform the following tasks:

Determine when to use a static or dynamic route.

Configure a static route on a Cisco Router. Describe how distance vector routing protocols operate.

Configure the RIP and IGRP routing protocols on a Ciscorouter.

Use showip route, show ip protocols, and other show anddebug commands to verify proper routing operation.


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Review Questions

1. What is an advantage of using a staticroute rather than a dynamic route?What is a disadvantage?

2. What is the advantage of using IGRPrather then RIP? What is a possibledisadvantage?

3. To scale up to very large IP networks,what routing protocols are recommended?

determining ip routes

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