交換路由CCIE之路――單進(jìn)程OSPF數(shù)據(jù)分流

1、實(shí)驗(yàn) 單進(jìn)程OSPF數(shù)據(jù)分流一實(shí)驗(yàn)拓?fù)?二實(shí)驗(yàn)需求實(shí)現(xiàn)去往生產(chǎn)業(yè)務(wù)（10.4.0.0）的數(shù)據(jù)走奇數(shù)路由器去往辦公業(yè)務(wù)（10.5.0.0）的數(shù)據(jù)走偶數(shù)路由器三實(shí)驗(yàn)分析首先全網(wǎng)用ospf 連通，這時(shí)候要進(jìn)行數(shù)據(jù)分流，就必須先了解各路由器中關(guān)于到生產(chǎn)和辦公存在的路由，然后再進(jìn)一步分析。全網(wǎng)運(yùn)行ospf后路由如下SW15SW16路由下一跳開銷路由下一跳開銷10.4.12.0直連10.4.12.0直連10.5.13.0直連10.5.13.0直連R1R2路由下一跳開銷路由下一跳開銷10.4.12.0SW15210.4.12.0SW16210.5.13.0SW15210.5.13.0SW162R3R4路由下

2、一跳開銷路由下一跳開銷10.4.12.0R15210.4.12.0R25210.5.13.0R15210.5.13.0R252R9R10路由下一跳開銷路由下一跳開銷10.4.12.0R310210.4.12.0R410210.5.13.0R310210.5.13.0R4102由上面可以看出所有數(shù)據(jù)分兩邊走，但是不是所需求的，現(xiàn)在要把數(shù)據(jù)分離開來(lái)，那么就必須使去往不同網(wǎng)段的路由改變。路由的選擇是先比較管理距離在比較開銷，這個(gè)時(shí)候運(yùn)行的都是OSPF管理距離是一樣的不能改，那么就改開銷。起初發(fā)現(xiàn)無(wú)論改哪條鏈路的開銷都不會(huì)有效，都會(huì)直接影響全部路由。這時(shí)候就要想到從源改起，那樣出來(lái)的路由就會(huì)有不同的開

3、銷了，而這里的源就是關(guān)于vlan16 vlan17的SVI口，我在SW15上將vlan16的開銷改為1000vlan17的開銷改為2000 ，在SW16上將vlan16的開銷改為2000vlan17的開銷改為1000 重新分析路由表SW15,SW16直連不變就分析了R1R2路由下一跳開銷路由下一跳開銷10.4.12.0SW15100110.4.12.0SW16100210.5.13.0SW15100210.5.13.0SW161001R3R4路由下一跳開銷路由下一跳開銷10.4.12.0R1105110.4.12.0R2 R3105210.5.13.0R1 R4105210.5.13.0R21

4、051R9R10路由下一跳開銷路由下一跳開銷10.4.12.0R3110110.4.12.0R4 R9110210.5.13.0R3 R10110210.5.13.0R41101這里有幾點(diǎn)要注意R1到10.5.13.0下一跳不會(huì)有2個(gè)，因?yàn)镺SPF內(nèi)部路由優(yōu)先于區(qū)域間路由，所以只會(huì)有一條下一跳指向SW15的。R2到10.4.12.0也一樣只有一條這時(shí)候發(fā)現(xiàn)R3關(guān)于10.5.13.0有2條下一跳分別為R1 ,R4,而我們需要的是走R4的，那么就來(lái)分析這條路由是怎么達(dá)到負(fù)載均衡的，R3關(guān)于這條路由是通過(guò)R1 R2發(fā)布3類信息得到，通過(guò)計(jì)算就得到了2條，實(shí)際上應(yīng)該有3條，因?yàn)镽3到R2其實(shí)有2條路，

5、只是這里有一條也是指向R1，這里到后面會(huì)分析。那么在不改動(dòng)10.4.12.0這條路開銷的情況下要使關(guān)于10.5.13.0開銷加大，使它指向R4就必須考慮這2條路由在哪里路徑是不同的。首先10.4.12.0是從SW15到R1到R3 10.5.13.0是從SW16到SW15到R1到R3.,當(dāng)然這里其實(shí)也要同時(shí)考慮R4關(guān)于這2條路由的開銷。這時(shí)候就很明顯的知道應(yīng)該改SW15與SW16間的開銷，這里我改為100，得到路由表應(yīng)該如下R1R2路由下一跳開銷路由下一跳開銷10.4.12.0SW15100110.4.12.0SW16110110.5.13.0SW15110110.5.13.0SW161001R

6、3R4路由下一跳開銷路由下一跳開銷10.4.12.0R1105110.4.12.0R2 R3 105210.5.13.0R1 R4105210.5.13.0R21051R9R10路由下一跳開銷路由下一跳開銷10.4.12.0R3110110.4.12.0R4 R9110210.5.13.0R3 R10110210.5.13.0R41101這時(shí)候發(fā)現(xiàn)R3到10.5.13.0還有2條，這就是我開始說(shuō)的隱藏的那一條了，就是因?yàn)榈絉2在區(qū)域內(nèi)會(huì)有負(fù)載均衡，所以會(huì)有2條，同樣按照上面的分析方法，要滿足需求就只能改R1 與R2之間的開銷，改為100，路由如下R1R2路由下一跳開銷路由下一跳開銷10.4.1

7、2.0SW15100110.4.12.0SW16110110.5.13.0SW15110110.5.13.0SW161001R3R4路由下一跳開銷路由下一跳開銷10.4.12.0R1105110.4.12.0R3105210.5.13.0R4105210.5.13.0R21051R9R10路由下一跳開銷路由下一跳開銷10.4.12.0R3110110.4.12.0R9 R4110210.5.13.0R3 R10110210.5.13.0R41101這時(shí)候R3 R4就滿足要求了，接下來(lái)看R9 R10 ,發(fā)現(xiàn)R9關(guān)于10.5.13.0走負(fù)載均衡，同樣的道理，下一跳指為R10的不能動(dòng)，因?yàn)槟鞘俏覀冃?/p>

8、要的，現(xiàn)在要使從R3來(lái)的開銷加大，但要是在R3到R9的鏈路上改開銷肯定是不行的，那樣會(huì)影響去往10.4.12.0的，那么只有再向上看，R3關(guān)于這一條是從R4來(lái)的，那么改R3與R4之間的開銷應(yīng)該就能達(dá)到要求了，不過(guò)這里在改開銷是一定要注意不能大于上面的100。否則可能是上面路由發(fā)生變化。將它改為50 ，路由如下R1R2路由下一跳開銷路由下一跳開銷10.4.12.0SW15100110.4.12.0SW16110110.5.13.0SW15110110.5.13.0SW161001R3R4路由下一跳開銷路由下一跳開銷10.4.12.0R1105110.4.12.01101R310.5.13.0R4

9、110110.5.13.0R21051R9R10路由下一跳開銷路由下一跳開銷10.4.12.0R3110110.4.12.0R9110210.5.13.0R10110210.5.13.0R41101這樣就達(dá)到了需求四 實(shí)驗(yàn)驗(yàn)證 OSPF配置查看路由表sw15#show ip routeC 10.5.13.0/24 is directly connected, Vlan17C 10.4.12.0/24 is directly connected, Vlan16sw16#show ip route C 10.5.13.0/24 is directly connected, Vlan17C 10.4

10、.12.0/24 is directly connected, Vlan16r1#show ip route O 10.5.13.0/24 110/2 via 10.1.9.5, 00:11:02, FastEthernet2/0O 10.4.12.0/24 110/2 via 10.1.9.5, 00:11:02, FastEthernet2/0r2#show ip routeO 10.5.13.0/24 110/2 via 10.1.9.9, 00:11:39, FastEthernet2/0O 10.4.12.0/24 110/2 via 10.1.9.9, 00:11:39, Fast

11、Ethernet2/0r3#show ip routeO IA 10.5.13.0/24 110/52 via 10.1.1.5, 00:05:01, Serial0/0O IA 10.4.12.0/24 110/52 via 10.1.1.5, 00:05:01, Serial0/0r4#show ip routeO IA 10.5.13.0/24 110/52 via 10.1.1.9, 00:05:25, Serial0/0O IA 10.4.12.0/24 110/52 via 10.1.1.9, 00:05:25, Serial0/0r9#show ip routeO IA 10.5

12、.13.0/24 110/102 via 10.1.41.5, 00:05:45, Serial0/0O IA 10.4.12.0/24 110/102 via 10.1.41.5, 00:05:45, Serial0/0r10#show ip routeO IA 10.5.13.0/24 110/102 via 10.1.41.9, 00:06:13, Serial0/0O IA 10.4.12.0/24 110/102 via 10.1.41.9, 00:06:13, Serial0/0與分析結(jié)果一樣更改vlan16 vlan17開銷sw15(config)#int vlan 16sw15

13、(config-if)#ip ospf cost 1000sw15(config-if)#int vlan 17sw15(config-if)#ip ospf cost 2000sw15(config-if)#endsw16(config)#int vlan 16sw16(config-if)#ip ospf cost 2000sw16(config-if)#int vlan 17sw16(config-if)#ip ospf cost 1000sw16(config-if)#end查看路由表sw15#show ip routeC 10.5.13.0/24 is directly connec

14、ted, Vlan17C 10.4.12.0/24 is directly connected, Vlan16sw16#show ip routeC 10.5.13.0/24 is directly connected, Vlan17C 10.4.12.0/24 is directly connected, Vlan16r1#show ip routeO 10.5.13.0/24 110/1002 via 10.1.9.5, 00:01:14, FastEthernet2/0/這里沒(méi)有負(fù)載均衡，因?yàn)镺SPF域內(nèi)路由優(yōu)于域間路由O 10.4.12.0/24 110/1001 via 10.1.9

15、.5, 00:01:14, FastEthernet2/0r2#show ip routeO 10.5.13.0/24 110/1001 via 10.1.9.9, 00:01:37, FastEthernet2/0O 10.4.12.0/24 110/1002 via 10.1.9.9, 00:01:37, FastEthernet2/0r3#show ip routeO IA 10.5.13.0/24 110/1052 via 10.1.1.14, 00:01:40, FastEthernet1/0 110/1052 via 10.1.1.5, 00:01:40, Serial0/0O I

16、A 10.4.12.0/24 110/1051 via 10.1.1.5, 00:01:50, Serial0/0r4#show ip routeO IA 10.5.13.0/24 110/1051 via 10.1.1.9, 00:01:55, Serial0/0O IA 10.4.12.0/24 110/1052 via 10.1.1.13, 00:02:05, FastEthernet1/0 110/1052 via 10.1.1.9, 00:02:05, Serial0/0r9#show ip routeO IA 10.5.13.0/24 110/1102 via 10.1.41.14

17、, 00:01:56, FastEthernet1/0 110/1102 via 10.1.41.5, 00:01:56, Serial0/0O IA 10.4.12.0/24 110/1101 via 10.1.41.5, 00:02:05, Serial0/0r10#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.41.9, 00:02:09, Serial0/0O IA 10.4.12.0/24 110/1102 via 10.1.41.13, 00:02:17, FastEthernet1/0 110/1102 via 10.1.41.

18、9, 00:02:17, Serial0/0接下來(lái)就是要解決這些負(fù)載均衡的路由了將SW15 SW16間開銷改為100sw15(config)#int vlan 901sw15(config-if)#ip ospf cost 100sw15(config-if)#endsw16(config)#int vlan 901sw16(config-if)#ip ospf cost 100sw16(config-if)#end查看路由表r1#show ip routeO 10.5.13.0/24 110/1101 via 10.1.9.5, 00:00:27, FastEthernet2/0 /域內(nèi)由于

19、域間，即使開銷大O 10.4.12.0/24 110/1001 via 10.1.9.5, 00:00:27, FastEthernet2/0r2#show ip routeO 10.5.13.0/24 110/1001 via 10.1.9.9, 00:00:39, FastEthernet2/0O 10.4.12.0/24 110/1101 via 10.1.9.9, 00:00:39, FastEthernet2/0r3#show ip routeO IA 10.5.13.0/24 110/1052 via 10.1.1.14, 00:01:07, FastEthernet1/0 110

20、/1052 via 10.1.1.5, 00:01:07, Serial0/0 /雖然和上面一樣是負(fù)載均衡但這里的路由都是由R2傳來(lái)的O IA 10.4.12.0/24 110/1051 via 10.1.1.5, 00:00:48, Serial0/0r4#show ip routeO IA 10.5.13.0/24 110/1051 via 10.1.1.9, 00:01:18, Serial0/0O IA 10.4.12.0/24 110/1052 via 10.1.1.13, 00:01:00, FastEthernet1/0 110/1052 via 10.1.1.9, 00:01:

21、00, Serial0/0r9#show ip routeO IA 10.5.13.0/24 110/1102 via 10.1.41.14, 00:13:23, FastEthernet1/0 110/1102 via 10.1.41.5, 00:13:23, Serial0/0O IA 10.4.12.0/24 110/1101 via 10.1.41.5, 00:13:32, Serial0/0r10#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.41.9, 00:13:34, Serial0/0O IA 10.4.12.0/24 11

22、0/1102 via 10.1.41.13, 00:13:42, FastEthernet1/0 110/1102 via 10.1.41.9, 00:13:42, Serial0/0從上向下一層一層的去掉負(fù)載均衡改R1 R2間開銷r1(config)#int f1/0r1(config-if)#ip ospf cost 100r1(config-if)#endr2(config)#int f1/0r2(config-if)#ip ospf cost 100r2(config-if)#end查看路由表r1#show ip routeO 10.5.13.0/24 110/1101 via 10.

23、1.9.5, 00:06:14, FastEthernet2/0O 10.4.12.0/24 110/1001 via 10.1.9.5, 00:06:14, FastEthernet2/0r2#show ip routeO 10.5.13.0/24 110/1001 via 10.1.9.9, 00:06:30, FastEthernet2/0O 10.4.12.0/24 110/1101 via 10.1.9.9, 00:06:30, FastEthernet2/0 r3#show ip routeO IA 10.5.13.0/24 110/1052 via 10.1.1.14, 00:0

24、0:25, FastEthernet1/0O IA 10.4.12.0/24 110/1051 via 10.1.1.5, 00:00:25, Serial0/0r4# show ip route O IA 10.5.13.0/24 110/1051 via 10.1.1.9, 00:01:15, Serial0/0O IA 10.4.12.0/24 110/1052 via 10.1.1.13, 00:01:15, FastEthernet1/0r9#show ip routeO IA 10.5.13.0/24 110/1102 via 10.1.41.14, 00:17:48, FastE

25、thernet1/0 110/1102 via 10.1.41.5, 00:17:48, Serial0/0O IA 10.4.12.0/24 110/1101 via 10.1.41.5, 00:17:57, Serial0/0r10#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.41.9, 00:17:58, Serial0/0O IA 10.4.12.0/24 110/1102 via 10.1.41.13, 00:18:06, FastEthernet1/0 110/1102 via 10.1.41.9, 00:18:06, Seri

26、al0/0R3 R4解決了接下來(lái)是R5 R6改RT3 RT4 間開銷為50 ，一定要記住不能改的和上面一樣那樣還是產(chǎn)生對(duì)稱從而使得R3 R4又出現(xiàn)負(fù)載均衡，也不能大于它，那樣就不滿足實(shí)驗(yàn)要求r3(config)#int f1/0r3(config-if)#ip ospf cost 50r3(config-if)#endr4(config)#int f1/0r4(config-if)#ip ospf cost 50 r4(config-if)#end查路由表r1#show ip routeO 10.5.13.0/24 110/1101 via 10.1.9.5, 00:12:04, FastEt

27、hernet2/0O 10.4.12.0/24 110/1001 via 10.1.9.5, 00:12:04, FastEthernet2/0r2#show ip routeO 10.5.13.0/24 110/1001 via 10.1.9.9, 00:12:08, FastEthernet2/0O 10.4.12.0/24 110/1101 via 10.1.9.9, 00:12:08, FastEthernet2/0r3#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.1.14, 00:00:05, FastEthernet1/0O I

28、A 10.4.12.0/24 110/1051 via 10.1.1.5, 00:00:05, Serial0/0 r4#show ip routeO IA 10.5.13.0/24 110/1051 via 10.1.1.9, 00:00:25, Serial0/0O IA 10.4.12.0/24 110/1101 via 10.1.1.13, 00:00:25, FastEthernet1/0 r9#show ip routeO IA 10.5.13.0/24 110/1102 via 10.1.41.14, 00:00:42, FastEthernet1/0O IA 10.4.12.0

29、/24 110/1101 via 10.1.41.5, 00:00:26, Serial0/0r10#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.41.9, 00:00:48, Serial0/0O IA 10.4.12.0/24 110/1102 via 10.1.41.13, 00:00:36, FastEthernet1/0問(wèn)題解決，和我的分析一致。數(shù)據(jù)流測(cè)試r10#traceroute 10.4.12.15 /到生產(chǎn)的數(shù)據(jù)Type escape sequence to abort.Tracing the route to 10.4.

30、12.15 1 10.1.41.13 952 msec 420 msec 72 msec 2 10.1.41.5 152 msec 64 msec 140 msec 3 10.1.1.5 576 msec 292 msec 172 msec 4 10.1.9.5 1604 msec 1212 msec * r10#traceroute 10.5.13.15 /到辦公的數(shù)據(jù)Type escape sequence to abort.Tracing the route to 10.5.13.15 1 10.1.41.9 208 msec 528 msec 396 msec 2 10.1.1.9 2

31、88 msec 136 msec 92 msec 3 10.1.9.9 380 msec 192 msec 184 msec 4 10.5.13.15 728 msec 984 msec * r10#traceroute 10.5.13.16Type escape sequence to abort.Tracing the route to 10.5.13.16 1 10.1.41.9 176 msec 260 msec 60 msec 2 10.1.1.9 528 msec 100 msec 444 msec 3 10.1.9.9 1240 msec 736 msec * r10#trace

32、route 10.4.12.16Type escape sequence to abort.Tracing the route to 10.4.12.16 1 10.1.41.13 300 msec 140 msec 108 msec 2 10.1.41.5 868 msec 220 msec 128 msec 3 10.1.1.5 1496 msec 196 msec 92 msec 4 10.1.9.5 716 msec 544 msec 356 msec 5 * 10.4.12.16 224 msec 696 msec鏈路切換將鏈路R9到R3的Downr9(config)#int s0/

33、0r9(config-if)#shur10#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.41.9, 00:00:12, Serial0/0O IA 10.4.12.0/24 110/1151 via 10.1.41.9, 00:00:12, Serial0/0 /R10關(guān)于生產(chǎn)的路由變了，但上面路由器的并沒(méi)變?nèi)阅軡M足要求r10#traceroute 10.4.12.16Type escape sequence to abort.Tracing the route to 10.4.12.16 1 10.1.41.9 128 msec 432

34、msec 224 msec 2 10.1.1.13 540 msec 184 msec 152 msec /轉(zhuǎn)到R3繼續(xù)上傳 3 10.1.1.5 232 msec 172 msec 228 msec 4 10.1.9.5 920 msec 548 msec 640 msec 5 10.4.12.16 680 msec 712 msec * r10#traceroute 10.5.13.15Type escape sequence to abort.Tracing the route to 10.5.13.15 1 10.1.41.9 272 msec 216 msec 120 msec 2

35、10.1.1.9 164 msec 684 msec 372 msec 3 10.1.9.9 608 msec 184 msec 156 msec 4 10.5.13.15 324 msec * 528 msecr10#traceroute 10.5.13.16Type escape sequence to abort.Tracing the route to 10.5.13.16 1 10.1.41.9 232 msec 108 msec 436 msec 2 10.1.1.9 664 msec 136 msec 388 msec 3 10.1.9.9 420 msec 448 msec 8

36、40 msecr10#r10#traceroute 10.4.12.15Type escape sequence to abort.Tracing the route to 10.4.12.15 1 10.1.41.9 180 msec 160 msec 92 msec 2 10.1.1.13 732 msec 508 msec 60 msec 3 10.1.1.5 500 msec 152 msec 204 msec 4 10.1.9.5 388 msec * 1324 msec如果R3與R1之間鏈路Down，那下面的路由都會(huì)發(fā)生改變r(jià)3(config)#int s0/0r3(config-

37、if)#shur10#show ip routeO IA 10.5.13.0/24 110/1101 via 10.1.41.9, 00:00:49, Serial0/0O IA 10.4.12.0/24 110/1201 via 10.1.41.9, 00:00:19, Serial0/0r9#show ip routeO IA 10.5.13.0/24 110/1102 via 10.1.41.14, 00:05:13, FastEthernet1/0O IA 10.4.12.0/24 110/1202 via 10.1.41.14, 00:04:39, FastEthernet1/0五實(shí)

38、驗(yàn)總結(jié)對(duì)單進(jìn)程OSPF的分流中改開銷值這種方法我感覺(jué)就像玩魔方，先找到突破口，即起始位置，然后一層一層去分析，到最后就得到了我們想要的結(jié)果。方法二利用詳細(xì)，匯總路由來(lái)解決需求實(shí)驗(yàn)分析我們知道數(shù)據(jù)流選路時(shí)只有一個(gè)原則最長(zhǎng)掩碼匹配原則，而OSPF間又可以進(jìn)行路由匯總，那么我可以通過(guò)在R1上匯總10.5.13.0網(wǎng)段的為10.5.0.0發(fā)布出來(lái)，而在R2上匯總10.4.12.0為10.4.0.0發(fā)布出來(lái)，這時(shí)候路由表如下R1R2路由下一跳開銷路由下一跳開銷10.4.0.0R2310.4.0.010.5.0.010.5.0.0R1310.4.12.0SW15210.4.12.0SW16210.5.13

39、.0SW15210.5.13.0SW162R3R4路由下一跳開銷路由下一跳開銷10.4.0.0R1 R45310.4.0.0R25210.5.0.0R15210.5.0.0R2 R35310.4.12.0R15210.4.12.0R2 R35310.5.13.0R1 R45310.5.13.0R252R9R10路由下一跳開銷路由下一跳開銷10.4.0.0R3 R1010310.4.0.0R410210.5.0.0R310210.5.0.0R4 R910310.4.12.0R310210.4.12.0R4 R910310.5.13.0R3 R10 10310.5.13.0R4102在R3發(fā)現(xiàn)了與

40、方法一同樣的負(fù)載均衡，這時(shí)候在按方法一的辦法改中間R1 R2 的開銷為100就得到如下路由R1R2路由下一跳開銷路由下一跳開銷10.4.0.0R210210.4.0.010.5.0.010.5.0.0R110210.4.12.0SW15210.4.12.0SW16210.5.13.0SW15210.5.13.0SW162R3R4路由下一跳開銷路由下一跳開銷10.4.0.0R45310.4.0.0R25210.5.0.0R15210.5.0.0R35310.4.12.0R15210.4.12.0R35310.5.13.0R45310.5.13.0R252R9R10路由下一跳開銷路由下一跳開銷10

41、.4.0.0R3 R1010310.4.0.0R410210.5.0.0R310210.5.0.0R4 R910310.4.12.0R310210.4.12.0R4 R910310.5.13.0R3 R10 10310.5.13.0R4102再改R3 R4開銷為50 就得到了滿足需求的路由R1R2路由下一跳開銷路由下一跳開銷10.4.0.0R210210.4.0.010.5.0.010.5.0.0R110210.4.12.0SW15210.4.12.0SW16210.5.13.0SW15210.5.13.0SW162R3R4路由下一跳開銷路由下一跳開銷10.4.0.0R410210.4.0.0

42、R25210.5.0.0R15210.5.0.0R310210.4.12.0R15210.4.12.0R310210.5.13.0R410210.5.13.0R252R9R10路由下一跳開銷路由下一跳開銷10.4.0.0R1010310.4.0.0R410210.5.0.0R310210.5.0.0R910310.4.12.0R310210.4.12.0R910310.5.13.0R10 10310.5.13.0R4102實(shí)驗(yàn)驗(yàn)證在R1上做匯總，將辦公網(wǎng)段匯成10.5.0.0在R2上做匯總，將業(yè)務(wù)網(wǎng)段匯成10.4.0.0r1(config)#router ospf 1r1(config-rou

43、ter)#area 1 range 10.5.0.0 255.255.0.0r1(config-router)#endr1#r2(config)#router ospf 1r2(config-router)#area 1 range 10.4.0.0 255.255.0.0r2(config-router)#end查路由表r1#show ip route O 10.5.13.0/24 110/2 via 10.1.9.5, 00:00:34, FastEthernet2/0O 10.4.12.0/24 110/2 via 10.1.9.5, 00:00:34, FastEthernet2/0O

44、 IA 10.4.0.0/16 110/3 via 10.1.1.2, 00:00:10, FastEthernet1/0/雖然有兩條到10.4網(wǎng)段的，但根據(jù)最長(zhǎng)掩碼匹配原則會(huì)選上面那條O 10.5.0.0/16 is a summary, 00:00:34, Null0r2#show ip routeO 10.5.13.0/24 110/2 via 10.1.9.9, 00:04:42, FastEthernet2/0O 10.4.12.0/24 110/2 via 10.1.9.9, 00:04:42, FastEthernet2/0O 10.4.0.0/16 is a summary,

45、00:04:42, Null0O IA 10.5.0.0/16 110/3 via 10.1.1.1, 00:04:42, FastEthernet1/0r3# show ip routeO IA 10.5.13.0/24 110/53 via 10.1.1.14, 00:03:08, FastEthernet1/0 110/53 via 10.1.1.5, 00:03:08, Serial0/0 /同樣這里會(huì)出現(xiàn)負(fù)載均衡，因?yàn)殒溌肥菍?duì)稱的O IA 10.4.12.0/24 110/52 via 10.1.1.5, 00:02:45, Serial0/0O IA 10.4.0.0/16 110

46、/53 via 10.1.1.14, 00:02:45, FastEthernet1/0 110/53 via 10.1.1.5, 00:02:45, Serial0/0O IA 10.5.0.0/16 110/52 via 10.1.1.5, 00:03:10, Serial0/0r4#show ip routeO IA 10.5.13.0/24 110/52 via 10.1.1.9, 00:03:43, Serial0/0O IA 10.4.12.0/24 110/53 via 10.1.1.13, 00:03:20, FastEthernet1/0 110/53 via 10.1.1.

47、9, 00:03:20, Serial0/0O IA 10.4.0.0/16 110/52 via 10.1.1.9, 00:03:20, Serial0/0O IA 10.5.0.0/16 110/53 via 10.1.1.13, 00:03:45, FastEthernet1/0 110/53 via 10.1.1.9, 00:03:45, Serial0/0r9#show ip routeO IA 10.5.13.0/24 110/103 via 10.1.41.14, 00:03:57, FastEthernet1/0 110/103 via 10.1.41.5, 00:03:57,

48、 Serial0/0O IA 10.4.12.0/24 110/102 via 10.1.41.5, 00:03:35, Serial0/0O IA 10.4.0.0/16 110/103 via 10.1.41.14, 00:03:35, FastEthernet1/0 110/103 via 10.1.41.5, 00:03:35, Serial0/0O IA 10.5.0.0/16 110/102 via 10.1.41.5, 00:03:58, Serial0/0r10#show ip routeO IA 10.5.13.0/24 110/102 via 10.1.41.9, 00:0

49、4:14, Serial0/0O IA 10.4.12.0/24 110/103 via 10.1.41.13, 00:03:51, FastEthernet1/0 110/103 via 10.1.41.9, 00:03:51, Serial0/0O IA 10.4.0.0/16 110/102 via 10.1.41.9, 00:03:51, Serial0/0O IA 10.5.0.0/16 110/103 via 10.1.41.13, 00:04:15, FastEthernet1/0 110/103 via 10.1.41.9, 00:04:15, Serial0/0通過(guò)改開銷來(lái)打破這種對(duì)稱性，和上面的方法一是一樣的。改R1R2之間鏈路開銷r1(config)#int f1/0r1(config-if)#ip ospf co 100r2(config)#int f1/0r2(config-if)#ip ospf co 100查路由表r1#show ip routeO 10.5.13.0/24 110/2 via 10.1.9.5, 00:07:33, FastEthernet2/0O 10.4.12.0/24 110/2 via 10.1.9.5, 00:07:33, FastEthernet2/0O IA 10.4.0.0/16 110/1