EIGRP
※ Why EIGRP? ※
因為上一代用IGRP太慢,
而BGP不會auto-summary route, 又不會快速搵alternate path.
※ Metric ※
Metric =
[K1*BW*256+(K2*BW)/(256-load)+K3*delay*256]*[K5/(realiability+K4)]
where BW =
107 Kbit / interface_bandwidth(Kbit), 請選取Path中最小BW
where delay =
interface_delay(usec) / 10, 請選取Path中delay總和
Default K Value:
K1=1, K2=0, K3=1, K4=0, K5=0
R1(config-router)#metric weights 0 5 2 1 10 1 //0,K1,K2,K3,K4,K5
Default Metric =
BW*256+delay*256
Wide Metric =
[K1*BW*256+(K2*BW)/(256-load)+K3*delay*256+K6*Extended_Attributes]*[K5/(realiability+K4)]
where BW =
107 Kbit *256 / interface_bandwidth(Kbit), 請選取Path中最小BW
where delay =
interface_delay(picosec)*256 / 10 0000, 請選取Path中delay總和
※ Route選擇 ※
R1# show ip eigrp topology all-links
P 7.7.7.7/32, 1 successors, FD is 435200
//Distance最短, FD
via 192.168.12.2 (435200/409600)
//Distance最短, Successor
via 192.168.14.4 (473600/448000)
//AD<FD, Feasible Successor
via 192.168.13.3 (437760/412160)
//AD>FD, Removed from Routing Table
※ Variance ※
FD多少倍以下Distance的Route 可放在Route Table Load-balance
※ Summarization ※
Default:
以class A/B/C 來 auto-summary
Manual:
R1(config-if)#ip summary-address eigrp 1 172.16.0.0 255.255.224.0
※ Leak-map ※
把summary route其中某些route 滲出來發佈
R1(config)#access-list 1 permit 10.0.1.0 0.0.0.255
R1(config)#route-map EIGRP-Leak
R1(config-route-map)#match ip address 1
R1(config)#int e0/0
R1(config)#ip summary-address eigrp 1 10.0.0.0 255.255.252.0 leak-map EIGRP-Leak
※ Query and Reply ※
如Successor及Feasible Successor都行不通:
向Neighbour 發Query Message, 等收Reply Message
發出Query Message後,
P轉A, 3分鐘沒Reply Message便會Stuck-in-active
P 172.16.0.0/16, 1 successor, FD is 409600
A 172.16.0.0/16, 1 successor, FD is 409600
※ Stub ※
成為stub後便不會接收Query Message
R2(config)#router eigrp 1
R2(config-router)#eigrp stub
//不接收Query及發佈Route
R2(config-router)#eigrp stub receive-only
//只接收及不發佈Route
R2(config-router)#eigrp stub connected
//只發佈Connected Route
R2(config-router)#eigrp stub redistributed
//只發佈Redistributed Route
R2(config-router)#eigrp stub static
//只發佈Static Route
R2(config-router)#eigrp stub summary
//只發佈Summary Route
※ Named Mode ※
傳統Mode:
R1(config)#router eigrp 1
R1(config-router)#no auto-summary
R1(config-router)#redistribute connected
R1(config-router)#network 192.168.12.0
R1(config-router)#eigrp stub redistributed
Named Mode:
R1(config)#router eigrp JANNET
R1(config-router)#address-family ipv4 unicast autonomous-system 1
R1(config-router-af)#af-interface e1/0
R1(config-router-af-int)#summary-address 192.168.1.0 255.255.255.0
R1(config-router-af-int)#exit-af-interface
R1(config-router-af)#topology base
R1(config-router-af-topo)#no auto-summary
R1(config-router-af-topo)#redistribute connected
R1(config-router-af-topo)#exit-af-topology
R1(config-router-af)#network 192.168.12.0
R1(config-router-af)#eigrp stub redistributed
R1(config-router-af)#exit-address-family
※ Metric Rib-scale ※
把只有入Eigrp table而沒有入route table的route 的metric scale細
R1(config)#route eigrp JANNET
R1(config-router)#address-family ipv4 autonomous-system 1
R1(config-router-af)#metric rib-scale 160