Cisco EIGRP

EIGRP är ett distance vector routing protokoll med en del karaktär av link state protocol. Det är protokoll utvecklat av Cisco, det har varit properitärt men är sedan 2013 släppt, dock bara som Informational RFC. EIGRP använder ett eget IP-protokoll (88) på lager 4, Reliable Transport Protocol. Det används båda för unicast och multicast. För topologiuträkningar används DUAL.

Databaser

• Neighbor table
• Topology table
• Routing (Forwarding) table

Adjacency

• Hello packet - Multicast 224.0.0.10, every 5 seconds.
• AS nummer måste vara samma på alla routrar.
• K values need to match in EIGRP AS domain in order for neighbours to form

Metric

• k1 = bandwidth
• k2 = load
• k3 = delay
• k4 = reliability
• k5 = MTU

Simplified default metric = bandwidth + delay

Konfiguration

router eigrp [ASN]
eigrp router-id 1.1.1.1
no auto-summary

Disable automatic route summarization (Default sedan IOS 15)

Neighbor

Interface vars IP-adress träffas av network-kommandot blir EIGRP-enabled.

network [ip-address] [wildcard-mask]

Designate passive interfaces.

passive-interface default
no passive-interface gi2

Statically identify neighoring routers. Kan behövas på vissa nätverkstyper.

neighbor [ip-address] [interface]

Max antal prefix från granne.

neighbor 10.0.1.1 maximum-prefix 100

Verify

show ip eigrp neighbors 

Authentication

MD5 authentication måste matcha för grannskap.

interface [interface]
ip authentication mode eigrp md5
ip authentication key-chain eigrp [ASN] [name-of-chain]

Default route

router eigrp 100
 ip default-network 10.0.0.0

default-information allowed

Summarization

Med EIGRP kan man summera var som helst.

ip eigrp summary-address 192.168.0.0 255.255.0.0

Filtering

Per prefix filtering med AD

access-list 7 permit 20.0.0.0
router eigrp 100
 distance 255 0.0.0.0 255.255.255.255 7

Träffar alla grannar

Others

4 paths default, 16 maximum

maximum-paths 12

Receive updates only

eigrp stub receive-only

BFD

router eigrp 100
 bfd interface gi2

Stänga av split horizon

int gi2
 no ip split-horizon eigrp 100

10% EIGRP-trafik

ip bandwidth-percent eigrp 100 10

timers graceful-restart purge-time 60

Adjust hop-count limit

metric maximum-hops 2

offset-lists

Redistribution

Default seed metric: infinity

Static

redistribute static

RIP

redistribute rip metric 1500 100 255 1 1500

OSPF

redistribute ospf 1

Named mode

Address Family section

router eigrp TEST
 address-family ipv4 unicast autonomous-system 100
  eigrp router-id 1.1.1.1

Per-AF-interface section

 af-interface Gi3
  authentication mode md5
  authentication key-chain cisco
 exit-af-interface

Per-AF-topology section

 topology base
  redistribute connected
 exit-af-topology

Show

show ip eigrp topology
show ip eigrp interfaces detail
show ip eigrp traffic
show ip protocols
show eigrp plugins