6.4.3设置最大的路径数
最大是16，缺省是4。
在网络中配置并行的路径时应该小心谨慎。太多的并行路径在某个链路失效时会增加EIGRP收敛时间，这是因为邻居路由器的数据也增加了，因此增加了查询范围。
路由器都是执行和这两条路径的路两只成反比的负载均衡
呜呜~~ 没有现成的图，他丫的我想偷懒！可以不 可以不 可以不
不可以~
不想自己画图
真心的
实验
3条链路，2条做负载均衡，一条失效，第三条替代失效的链路
根据计算算出v等于11
Johnson#sh run | be eigrp
router eigrp 100
variance 11
network 172.18.0.0
network 172.20.0.0
auto-summary
这边你可以看到所有的路由表
这边我们可以看到3条链路都在里面了
要满足情况要，只能有2条在链路中这样实现
router eigrp 100
variance 11
network 172.18.0.0
network 172.20.0.0
maximum-paths 2
auto-summary
再次查看路由表
查看3条链路，2条做负载均衡，一条失效，第三条替代失效的链路
Johnson#debug eigrp neighbors
EIGRP Neighbors debugging is on
Johnson#sh ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.18.0.0/16 is variably subnetted, 2 subnets, 2 masks
D 172.18.0.0/16 is a summary, 00:03:07, Null0
C 172.18.1.0/24 is directly connected, Loopback0
172.20.0.0/16 is variably subnetted, 5 subnets, 3 masks
C 172.20.15.20/30 is directly connected, Serial1/2
C 172.20.15.16/30 is directly connected, Serial1/1
D 172.20.10.0/24 [90/2297856] via 172.20.15.14, 00:03:07, Serial1/0
[90/10639872] via 172.20.15.18, 00:03:07, Serial1/1
D 172.20.0.0/16 is a summary, 00:03:07, Null0
C 172.20.15.12/30 is directly connected, Serial1/0
Johnson#conf t
Johnson(config)#int s1/0
Johnson(config-if)#sh
*May 2 21:57:18.203: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 100: Neighbor 172.20.15.14 (Serial1/0) is down: interface down
*May 2 21:57:18.211: EIGRP: Neighbor 172.20.15.14 went down on Serial1/0
*May 2 21:57:20.115: %LINK-5-CHANGED: Interface Serial1/0, changed state to administratively down
*May 2 21:57:21.115: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/0, changed state to down
Johnson#
Johnson#sh ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.18.0.0/16 is variably subnetted, 2 subnets, 2 masks
D 172.18.0.0/16 is a summary, 00:03:28, Null0
C 172.18.1.0/24 is directly connected, Loopback0
172.20.0.0/16 is variably subnetted, 5 subnets, 3 masks
C 172.20.15.20/30 is directly connected, Serial1/2
C 172.20.15.16/30 is directly connected, Serial1/1
D 172.20.10.0/24 [90/10639872] via 172.20.15.18, 00:00:09, Serial1/1
[90/20640000] via 172.20.15.22, 00:00:09, Serial1/2
D 172.20.0.0/16 is a summary, 00:00:09, Null0
D 172.20.15.12/30 [90/21024000] via 172.20.15.22, 00:00:09, Serial1/2
[90/11023872] via 172.20.15.18, 00:00:09, Serial1/1
Johnson#un all
第一2个做负载均衡
第二替换过来了
