by douglas kempthorne

EIGRP EIGRP EIGRP EIGRP ● Part 2

v1.0

Default Route RedistributionDefault Route RedistributionDefault Route RedistributionDefault Route Redistribution

www.hyper.org

! Classfull Default Gateway - Flag a route as a ‘candidate default’ ! (* in show ip route) - no 0.0.0.0/0 route in the EIGRP Topology Table ! Requires that the classfull network is also advertised ! R(config)# ip default-network IP Network

! Static Route redistribution - use route-maps to control if required R(config)# ip route 0.0.0.0 0.0.0.0 x.x.x.x R(config)# router eigrp ASN R(config-router)# redistribute static

Adjacency RequirementsAdjacency RequirementsAdjacency RequirementsAdjacency Requirements

• Authentication (None or MD5)

• ASN Number

• Primary IP Networks must be the same (secondary addresses will not work, incorrect netmask MAY work)

• K-Values must match

• Hello/Hold timers do not need

to match. The timers configured dictate “your” intervals to your neighbor and vice-versa.

Default TimersDefault TimersDefault TimersDefault Timers

High-Speed Interfaces 5 Second Hello, 3x [15s] Hold Low-Speed Interfaces (FR, PtMP) 60 Second Hello, 3x [180s] Hold ! Per-Interface Configuration R(config-if)# ip hello-interval eigrp ASN Seconds R(config-if)# ip hold-time eigrp ASN Seconds

SummarizationSummarizationSummarizationSummarization ! Classfull Auto-summarization ON by default R(config-router)# no auto-summary

! Per-Interface manual summarization at ANY POINT in the network R(config-if)# ip summary-address eigrp ASN ADDRESS NETMASK

Filtering RoutesFiltering RoutesFiltering RoutesFiltering Routes

! Applied under ‘router eigrp ASN’, with per-interface specification allowed distribute-list {access-list-number | name} {in | out} [interface-type interface-number] distribute-list {prefix list-name} {in | out} [interface-type interface-number]

variance Unequal-cost load balancing

maximum-paths {1..6} Defaults to 4

traffic-share balanced Balanced across routes, more packets for lower-cost routes.

traffic-share min Sends traffic using only lower-metric route

traffic-share balanced across-interfaces

When paths exceed maximum-paths, prefer routes on differing interfaces.

no traffic-share Balances evenly across all routes, ignore metrics.

Hello

Update Route Advertisement

ACK Acknowledge of Update

Query Request for a route Multicast to Neighbors Unicast to Non-responsive Neighbors

Reply Answer to a query

Packet TypesPacket TypesPacket TypesPacket Types

Load BalancingLoad BalancingLoad BalancingLoad Balancing

Convergance FunctionConvergance FunctionConvergance FunctionConvergance Function DescriptionDescriptionDescriptionDescription

Reported Distance [RD] Metric/Distance as reported by Neighbor

Feasible Distance [FD] Metric value for the lowest-metric path to reach a specific subnet.

Feasibility Condition In the case of multiple routes, if a route’s RD is less than the FD, it meets the Feasibility Condition.

Successor Route Lowest metric route(s)

Feasible successor [FS] A route that is not the lowest metric, but meets the Feasibility Condition and can be used should the Successor Route fail (is a loop-free path)

Input Event Any event that can cause the EIGRP topology to change.

Local Computation EIGRP reaction to an Input Event. Install FS or go active on a route.