Synergon Informatika Rt.

Chapter 11

Configuring Enhanced IGRP

Objectives

Upon completion of this chapter, you will be able to perform the following tasks:

Describe Enhanced IGRP features and operation

Configure Enhanced IGRP

Verify Enhanced IGRP operation

Enhanced IGRP

Operation

Enhanced IGRP Overview

Enhanced IGRP supports:

Rapid convergence

Partial bounded updates

Multiple network-layer support

Enhanced IGRP

IP Routing Protocols

IP Routing Protocols

AppleTalk RTMP AppleTalk RTMP

Novell Routing Protocols

Novell Routing Protocols

Enhanced IGRP Convergence

Neighbor B provides the best route to network 7

Neighbor B is in the routing table

D

H

B

A

Neighbor Table Topology Table

Network 7

NeighborB

Routing Table

Network 7

Network 7

Partial Bounded Updates

Updates only sent to directly connected neighbor

D

H

B

XX A

Update

Update

Update

Neighbor Discovery

D

H

B

A

Neighbor Table Topology Table

Network 7

NeighborB

Routing Table

B D H

Network 7

Topology Table

B is current successor router

H is the feasible successor

D

H

B

A

Network 7

(20)

(10)

(10)

(10)

(1)

(100) (100)

C

E F

G

Network 77

7

Advert. Distance21

220

30

NeighborBD

H

Feasible Dist.31

230

40

Topolog Table

Feasible Successor Selection

Router H becomes the successor

D

H

B

A

Network 7

(20)

(10)

(10)

(10)

(1)

(100) (100)

C

E F

G

Network 77

7

Advert. Distance21

220

30

NeighborBD

H

Feasible Dist.31

230

40

Active State

The route to network 7 change to Active state, Because no feasible successor exists

D

H

B

A

Network 7

(30)

(10)

(10)

(10)

(1)

(100) (100)

C

E F

G

Network 77

7

Advert. Distance21

220

40

NeighborBD

H

Feasible Dist.31

230

50

XX

Multiple Protocol Support for Novell IPX

IPX RIP IPX RIP

SAP Updates SAP Updates

Enhanced IGRP

Multiple Protocol Support for AppleTalk

RTMP RTMP

Enhanced IGRP

Multiple Protocol Support for IP

IPX RIP IPX RIP

Enhanced IGRP

AutonomousSystem 200

IGRP

AutonomousSystem 200

Enhanced IGRP

Enhanced IGRP

Configuration

Enhanced IGRP for IP Configuration

Router (config) #

router eigrp autonomous-system-numberrouter eigrp autonomous-system-number

• Defines Enhanced IGRP as an IP routing process

Router (config-router) #

network network-numbernetwork network-number

• Selects participating attached networks

Enhanced IGRP for IP Example

TokenRing

TokenRing

2.4.0.0

3.1.0.0

1.1.0.0

1.2.0.0

1.4.0.0

T0

2.3.0.0

2.1.0.02.2.0.0

2.5.0.0

2.6.0.0

2.7.0.0

S0

S1

S2

A

A

B

B

C

E

D

router eigrp 109 network 1.0.0.0 network 2.0.0.0

Integrating Enhanced IGRP

Enhanced IGRPIP RIP

IP RIP

AppleTalk RTMPAppleTalk RTMP

IPX RIP IPX RIP

• Enhanced IGRP saves WAN link by sending incremental routing updates

Enhanced IGRP Path Selection

Enhanced IGRP uses a composite metric to pick

the best path

IP RIP

AppleTalk RTMP

IPX RIP

IP RIP

AppleTalk RTMP

IPX RIP

Enhanced IGRP

19.2

T1

T1

T1

Integrated IPX Configuration

Router (config) #

ipx routing ipx routing

• Turns on IPX routing

Router (config) #

ipx router { eigrp autonomous-system-number | rip }ipx router { eigrp autonomous-system-number | rip }

• Selects a routing protocol for use by ipx

Integrated IPX Example

IPX

RIP

Network 10

Enhanced IGRP

E0 S0

Network 20

ipx routinginterface ethernet 0ipx network 10!interface serial 0ipx network 20!ipx router ripno network 20!Ipx router eigrp 1network 20

• Only EIGRP is active on network 20

IPX Incremental SAPs with Enhanced IGRP

IPX

RIP

Enhanced IGRP

E0 S0

Periodic

SAP updates

Incremental

SAP updates

• Non-Cisco systems are sensitive to incremental SAP updates

• Multiaccess media interfaces default to periodic updates

• Point-to-point interfaces default to incremental updates

SAP Update Configuration

Router (config-if) #

ipx sap-incremental eigrp autonomous-system-number [ rsup-only ]ipx sap-incremental eigrp autonomous-system-number [ rsup-only ]

• Forces a LAN interface to send incremental SAP updates

• Used to override SAP update defaults

• Assumes the presence of another Cisco router on that LAN

IPX Incremental SAP Example

FDDI Dual Ring

FDDI Dual Ring

Network 20

Network 10

IPX

RIP

F0

F0

F0S0

No IPX hosts on

FDDI backbone

Ipx routing

!

ipx router eigrp 1

network 10

network 20

!

ipx router rip

no network 10

no network 20

!

interface fddi 0

ipx network 10

ipx sap-incremental eigrp 1

!

Interface serial 0

ipx network 20

• Enables incremental-only SAP updates on an Enhanced IGRP FDDI backbone to conserve bandwidth

Integrated AppleTalk Configuration

Router (config) #

appletalk routing { eigrp router-number }appletalk routing { eigrp router-number }

• Turns on Enhanced IGRP for AppleTalk routing- Router-number must be unique for each router in the AppleTalk internetwork

Router (config-if) #

appletalk protocol eigrpappletalk protocol eigrp

• Selects Enhanced IGRP as the protocol that generates routing updates on this interface- Requires the AppleTalk cable range be specified first

Integrated Apple Talk Example

AppleTalk

E0S0

Enhanced IGRP

Only RTMP is

active, on by default

RTMP is turned off,

only EIGRP is active

appletalk routing eigrp 1 !Interface ethernet 0appletalk cable-range 10-10-10.51appletalk zone Headquarters!interface serial 0appletalk cable-range 111-111 111.51appletalk zone Shippingappletalk protocol eigrpno appletalk protocol rtmp

Redistribution with Enhanced IGRP

Enhanced IGRPIP

IP

AppleTalkAppleTalk

IPX IPX

• Novell protocol redistribution with Enhanced IGRP is enabled by default

• AppleTalk RTMP redistribution is enabled by default

• Redistribution of IGRP in the same autonomous system is automatic

• Other protocols require redistribution

IP Route Redistribution

Routes are learned from another routing protocol

IP Routing Table

I 192.168.5.0 I 172.16.1.0 I 172.16.2.0 I 172.16.3.0

IP Routing Table

D EX 192.168.5.0 D 192.168.5.8 D 192.168.5.16 D 192.168.5.24

S1 advertises routes from EIGRP

S0 advertises routes from EIGRP

AS 200 IGRP 172.16.0.0

AS Boundary Router

AS 200 IGRP

172.16.0.0

AS 300 EIGRP

192.168.5.0

S1 S0

IP Route Redistribution Configuration

Router (config-router) #

redistribute protocol [option]redistribute protocol [option]

• Allows routes discovered by one process to be advertised in the updates of another process

Router (config-router) #

default-metric bandwidth delay reliabulity loading mtudefault-metric bandwidth delay reliabulity loading mtu

• Used for IGRP and Enhanced IGRP redistribution

Router (config-router) #

default-metric numberdefault-metric number

• Used for OSPF, RIP, EGP BGP redistribution

IGRP to Enhanced IGRP Migration

Autonomous System 100

IGRP/EIGRP

Automatic

redistribution

Autonomous System 200

IGRP

Autonomous System 300

EIGRPRedistribution configuration

required

• Enhanced IGRP sends updates that are not compatible with IGRP full table updates

• Redistribution is automatic within the same autonomous systems

• Manual redistribution is required between autonomous systems

IP Route Redistribution Example 1AS 200

IGRP

172.16.0.0

AS 300

EIGRP

192.168.5.0

router eigrp 300

network 192.168.5.0

redistribute igrp 200

!

route igrp 200

network 172.16.0.0redistribute eigrp 300

• default-metric command is optional with IGRP/EIGRP redistribution

IP Route Redistribution Example 2

RIP

172.68.0.0

AutonomousSystem 300

EIGRP201.222.5.0

router rip

network 172.68.0.0

redistribute eigrp 300

default-metric 3

route eigrp 300

network 201.222.5.0

redistribute rip

default-metric 56 2000 255 1 1500

Minimizing Routing Updates

Route Filtering

Router (config-router) #

distribute-list access-list-number { out | in }

[ interface-name | routing-process ]

distribute-list access-list-number { out | in }

[ interface-name | routing-process ]

• Specifies routes passed to the receiving routing protocol

• Uses a standard access list to permit or deny routes

• Can be applied to transmitted (outbound) or received (inbound) routing updates

• Filters all updates or updates on specific interfaces

IP Route Filtering Example

Hides network 10.0.0.0 using interface filtering

router eigrp 1network 172.16.0.0network 192.168.5.0distribute-list 7 out s0!Access-list 7 permit 172.16.0.0 0.0.255.255

10.0.0.0

172.16.0.0

192.168.5.0

IPX Route Filtering Example

Network 9e

Network 6c

Network 4a

Network 82

ipx router eigrp 100network 9enetwork 6cnetwork 4anetwork 82distribute-list 800 out s0!access-list 800 permit 6caccess-list 800 deny -1

ipx router eigrp 100network 9enetwork 6cnetwork 4anetwork 82distribute-list 800 out s0!access-list 800 permit 6caccess-list 800 deny -1

• Only network 6c is advertised in routing updates

Redistribution Filter Example

router ripnetwork 192.168.5.0 redistribute eigrp 1deafult-metric 3distribute-list out eigrp 7!router eigrp 1network 172.16.0.0redistribute ripdefault-metric 56 2000 255 1 1500!access-list 7 deny 10.0.0.0 0.255.255.255access-list 7 permit 0.0.0.0 255.255.255.255

RIP 192.168.5.0

EIGRP 172.16.0.0

EIGRP 10.0.0.0

• Hides network 10.0.0.0 using redistribution filtering

Enhanced IGRP Route Summarization

Router (config-router) #

no auto-summaryno auto-summary

• Network-level route summarization (Class A, B, or C) is enabled by default

• Disables automatic summarization

Router (config-if) #

ip summary-address eigrp as-number addresss maskip summary-address eigrp as-number addresss mask

• Enables summarization for advertisements on a specific interface

Route Summarization Example

router eigrp 1network 10.108.0.0network 172.16.0.0no auto-summary

router eigrp 1network 10.108.0.0endint s 0ip address 192.168.4.2 255.255.255.0ip summary-address eigrp 1 172.16.0.0 255.255.0.0

10.108.0.0

172.16.1.0

172.16.2.0

192.168.4.2

WorldS0

Minimizing Routing Updates

Router (config-router) #

passive-interface interface-namepassive-interface interface-name

• Prevent routing protocol updates from being generated on the interface

• As an alternative to passive interface you:

Do not configure a routing protocol on the interface

Use access lists to filter routing protocol

Use route redistribution

Using the passive-interface Command

The passive-interface command disables sending

routing updates on interfaces

RIP 172.17.0.0

EIGRP 172.16.0.0

AS 90

S0

E0

router ripnetwork 172.17.0.0redistribute eigrp 90default-metric 3pasive-interface ethernet 0!router eigrp 90network 172.16.0.0redistribute ripdefault-metric 1544 100 255 1 1500passive-interface serial 0

Static Route ConfigurationRouter (config) #

ip route network [ mask ] address [ distance ]ip route network [ mask ] address [ distance ]

• Defines a path to an IP destination network or subnet

• Default administrative distance is 1• Requires redistribution Router (config) #

ip route network [ mask ] interface [ distance ]ip route network [ mask ] interface [ distance ]

• Defines a path to an IP destination network or subnet

• Default administrative distance is 0 (means directly connected)

• Automatically redistributed

Static Route Reditribution

A

E D

B CS0

201.222.5.0 131.108.0.0

192.31.7.10 192.31.7.18

ip route 131.108.0.0 255.255.0.0 192.31.7.18ip route 201.222.5.0 255.255.255.0 192.31.7.10!router eigrp 1network 192.31.7.0default-metric 10000 100 255 1 1500redistribute staticdistribute-list 3 out static!access-list 3 permit 131.108.0.0 0.0.255.255

Passive-interface s0Passive-interface s0

VerifyingEnhanced IGRP Operation

Verifying Enhanced IGRP Operation

Router (config) #

show ip protocolsshow ip protocols

• Display the parameters and current state of the active routing protocol process

Router (config) #

show ip route eigrpshow ip route eigrp

• Display current Enhanced EIGRP entries in the routing table

Verifying Enhanced IGRP Operation (cont.)

Router (config) #

show ip eigrp neighborsshow ip eigrp neighbors

• Display the neighbours discovered by IP Enhanced IGRP

Router (config) #

show ip eigrp topologyshow ip eigrp topology

• Display the IP Enhanced IGRP topology table

Router (config) #

show ip eigrp trafficshow ip eigrp traffic

• Display the number of IP Enhanced IGRP packets sent and received

Verifying Enhanced IGRP Operation (cont.)

Router #

show ipx route show ipx route

• Displays the contents of the IPX routing table

Router #

show ipx eigrp neighborsshow ipx eigrp neighbors

• Display the neighbors discovered by IPX Enhanced IGRP

Router #

show ipx eigrp topologyshow ipx eigrp topology

• Displays the IPX Enhanced IGRP topology table

Verifying Enhanced IGRP Operation (cont.)

Router #

show AppleTalk route show AppleTalk route

• Displays the contents of the AppleTalk routing table

Router #

show AppleTalk eigrp neighborsshow AppleTalk eigrp neighbors

• Display the neighbors discovered by AppleTalk Enhanced IGRP

Router #

show AppleTalk eigrp topologyshow AppleTalk eigrp topology

• Displays the AppleTalk Enhanced IGRP topology table

Summary

Enhanced IGRP is an advanced routing

protocol that uses the DUAL algorithm

Enhanced IGRP has the following features:

Rapid convergence

Incremental updates

Routes IP, IPX, and AppleTalk

Route summarization