产品好 2007-11-13 09:59
关于IS-IS协议中的一些问题？
[img=448,286]http://www.one-tom.com/bbs/uploads/20061224_025211_isis.jpg[/img]
引用等级二实验手册下册P94页中的一段话：
在显示数据库输出的最后，有个ATT位，即区域关联位（Attached，ATT），[b][color=#ff0000]当L1/L2路由器R2发送它的L1 LSP（链路状态数据包，相当于OSPF的LSA）进入一个区域时，会在LSP中设置ATT位为1，代表通知其他L1路由器可以到达其他区域，有了这个通[/color][color=#ff0000]知，L1的路由器会安装默认路由[/color][/b]，按照（TCP/IP路由卷一）这本书的说法这个ATT位时CLNS的特性，IP协议并不能直接理解该位，解决问题需在R2和R3的链路上运行CLNS路由（在接口上配置clns router isis），但现在的IOS不需要做这个配置！
[font=宋体][size=9pt]依照上面的定义做了个实验！拓扑如上图：[/size][/font][size=9pt][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[font=宋体][size=9pt]配置如下[/size][/font][font=宋体][size=9pt]：[/size][/font][size=9pt][/size]
[b][size=9pt][font=Times New Roman]hostname R1[/font][/size][/b]
[size=9pt][font=Times New Roman]interface Loopback0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 1.1.1.1 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
[color=red]ip router isis [/color][/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Ethernet0/0[/font][/size]
[size=9pt][font=Times New Roman]
no ip address[/font][/size]
[size=9pt][font=Times New Roman]
shutdown[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 12.1.1.1 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]
clock rate 64000[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 13.1.1.1 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
[color=red]ip router isis [/color][/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]router isis [/font][/size]
[size=9pt][font=Times New Roman]net 47.0001.0000.0000.0001.00[/font][/size]
[size=9pt][font=Times New Roman]
is-type level-2-only[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]ip classless[/font][/size]
[size=9pt][font=Times New Roman]no ip http server[/font][/size]
[size=9pt][font=Times New Roman]no ip http secure-server[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[b][size=9pt][font=Times New Roman]hostname R2[/font][/size][/b]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Loopback0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 2.2.2.2 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Ethernet0/0[/font][/size]
[size=9pt][font=Times New Roman]
no ip address[/font][/size]
[size=9pt][font=Times New Roman]
shutdown[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 24.1.1.2 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
[color=red]ip router isis [/color][/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]
clock rate 64000[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 12.1.1.2 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]router isis [/font][/size]
[size=9pt][font=Times New Roman]
[color=red]net 47.0001.0000.0000.0002.00[/color][/font][/size]
[size=9pt][font=Times New Roman]
is-type level-2-only[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]ip classless[/font][/size]
[size=9pt][font=Times New Roman]no ip http server[/font][/size]
[size=9pt][font=Times New Roman]no ip http secure-server[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[b][size=9pt][font=Times New Roman]hostname R3[/font][/size][/b]
[size=9pt][font=Times New Roman]interface Loopback0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 3.3.3.3 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Ethernet0/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 10.1.1.3 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 13.1.1.3 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]
clock rate 64000[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 35.1.1.3 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]router isis [/font][/size]
[size=9pt][font=Times New Roman]
[color=red]net 48.0001.0000.0000.0003.00[/color][/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]ip classless[/font][/size]
[size=9pt][font=Times New Roman]no ip http server[/font][/size]
[size=9pt][font=Times New Roman]no ip http secure-server[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[b][size=9pt][font=Times New Roman]hostname R4[/font][/size][/b]
[size=9pt][font=Times New Roman]interface Loopback0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 4.4.4.4 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Ethernet0/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 10.1.1.4 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 45.1.1.4 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
[color=red]ip router isis [/color][/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]
clock rate 64000[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 24.1.1.4 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]router isis [/font][/size]
[size=9pt][font=Times New Roman]
net 48.0001.0000.0000.0004.00[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]ip classless[/font][/size]
[size=9pt][font=Times New Roman]no ip http server[/font][/size]
[size=9pt][font=Times New Roman]no ip http secure-server[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[b][size=9pt][font=Times New Roman]hostname R5[/font][/size][/b]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]!interface Loopback0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 5.5.5.5 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Ethernet0/0[/font][/size]
[size=9pt][font=Times New Roman]
no ip address[/font][/size]
[size=9pt][font=Times New Roman]
shutdown[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 35.1.1.5 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]
clock rate 64000[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]interface Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
ip address 45.1.1.5 255.255.255.0[/font][/size]
[size=9pt][font=Times New Roman]
ip router isis [/font][/size]
[size=9pt][font=Times New Roman]
serial restart-delay 0[/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]router isis [/font][/size]
[size=9pt][font=Times New Roman]
net 48.0001.0000.0000.0005.00[/font][/size]
[size=9pt][font=Times New Roman]
[color=red]is-type level-1[/color][/font][/size]
[size=9pt][font=Times New Roman]![/font][/size]
[size=9pt][font=Times New Roman]ip classless[/font][/size]
[size=9pt][font=Times New Roman]no ip http server[/font][/size]
[size=9pt][font=Times New Roman]no ip http secure-server[/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[font=宋体][size=9pt]配置没有问题，用[/size][/font][size=9pt][font=Times New Roman]show isis data[/font][/size][font=宋体][size=9pt]命令查看[/size][/font][size=9pt][font=Times New Roman]R3[/font][/size][font=宋体][size=9pt]的数据库：[/size][/font][size=9pt][/size]
[size=9pt][font=Times New Roman]R3#sho isis dat[/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman]IS-IS Level-1 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
* 0x00000006
0xFF43
1087
[color=red]
1[/color]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
0x00000009
0xBC65
1090
[color=red]
1[/color]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.01-00
0x00000001
0xBC8E
937
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x00000007
0xA51B
1090
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]IS-IS Level-2 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R1.00-00
0x00000005
0x4DD1
879
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R2.00-00
0x00000005
0xE822
925
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
* 0x00000009
0x7DE3
1089
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
0x0000000C
0x2136
1097
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.01-00
0x00000001
0x4C87
937
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x00000006
0x2D20
1006
0/0/0[/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman]R4[/font][/size][font=宋体][size=9pt]的数据库如下：[/size][/font][size=9pt][/size]
[size=9pt][font=Times New Roman]IS-IS Level-1 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
0x00000006
0xFF43
1068
[b][color=red]
1[/color][/b]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
* 0x00000009
0xBC65
1075
[b][color=red]
1[/color][/b]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.01-00
* 0x00000001
0xBC8E
921
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x00000007
0xA51B
1071
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]IS-IS Level-2 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R1.00-00
0x00000005
0x4DD1
860
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R2.00-00
0x00000005
0xE822
911
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
0x00000009
0x7DE3
1069
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
* 0x0000000C
0x2136
1081
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.01-00
* 0x00000001
0x4C87
921
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x00000006
0x2D20
989
0/0/0[/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[font=宋体][size=9pt]数据库正确说明：属于[/size][/font][size=9pt][font=Times New Roman]L1/L2[/font][/size][font=宋体][size=9pt]的路由器[/size][/font][size=9pt][font=Times New Roman]R3[/font][/size][font=宋体][size=9pt]和[/size][/font][size=9pt][font=Times New Roman]R4[/font][/size][font=宋体][size=9pt]分别向属于[/size][/font][size=9pt][font=Times New Roman]L1[/font][/size][font=宋体][size=9pt]的路由器[/size][/font][size=9pt][font=Times New Roman]R5[/font][/size][font=宋体][size=9pt]发送了[/size][/font][size=9pt][font=Times New Roman]L1 LSP[/font][/size][font=宋体][size=9pt]，当[/size][/font][size=9pt][font=Times New Roman]R5[/font][/size][font=宋体][size=9pt]收到[/size][/font][size=9pt][font=Times New Roman]L1 LSP[/font][/size][font=宋体][size=9pt]时会在路由表中安装一条默认路由！！[/size][/font][size=9pt][/size]
[size=9pt][font=Times New Roman]R5[/font][/size][font=宋体][size=9pt]的路由表：[/size][/font][size=9pt][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman]
35.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]C
35.1.1.0 is directly connected, Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
3.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]i L1
3.3.3.0 [115/20] via 35.1.1.3, Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
4.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]i L1
4.4.4.0 [115/20] via 45.1.1.4, Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
5.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]C
5.5.5.0 is directly connected, Loopback0[/font][/size]
[size=9pt][font=Times New Roman]
24.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]i L1
24.1.1.0 [115/20] via 45.1.1.4, Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
10.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]i L1
10.1.1.0 [115/20] via 35.1.1.3, Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
[115/20] via 45.1.1.4, Serial2/0[/font][/size]
[size=9pt][font=Times New Roman]
13.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]i L1
13.1.1.0 [115/20] via 35.1.1.3, Serial1/0[/font][/size]
[size=9pt][font=Times New Roman]
45.0.0.0/24 is subnetted, 1 subnets[/font][/size]
[size=9pt][font=Times New Roman]C
45.1.1.0 is directly connected, Serial2/0[/font][/size]
[b][size=9pt][font=Times New Roman]i*L1 0.0.0.0/0 [115/10] via 35.1.1.3, Serial1/0[/font][/size][/b]
[size=9pt][font=Times New Roman]
[b][color=red][115/10] via 45.1.1.4, Serial2/0[/color][/b][/font][/size]
[b][font=宋体][size=9pt]这时我们改变一下配置，我们把[/size][/font][/b][b][size=9pt][font=Times New Roman]5[/font][/size][/b][b][font=宋体][size=9pt]台路由器的[/size][/font][/b][b][size=9pt][font=Times New Roman]NET[/font][/size][/b][b][font=宋体][size=9pt]地址的区域号全部改成[/size][/font][/b][b][size=9pt][font=Times New Roman]47[/font][/size][/b][b][font=宋体][size=9pt]。[/size][/font][/b][b][size=9pt][font=Times New Roman]0001[/font][/size][/b]
[b][font=宋体][size=9pt]这时，[/size][/font][/b][b][size=9pt][font=Times New Roman]R3[/font][/size][/b][b][font=宋体][size=9pt]和[/size][/font][/b][b][size=9pt][font=Times New Roman]R4[/font][/size][/b][b][font=宋体][size=9pt]不会向[/size][/font][/b][b][size=9pt][font=Times New Roman]R5[/font][/size][/b][b][font=宋体][size=9pt]发送[/size][/font][/b][b][size=9pt][font=Times New Roman]L1 LSP[/font][/size][/b][b][font=宋体][size=9pt]，所以[/size][/font][/b][b][size=9pt][font=Times New Roman]R5[/font][/size][/b][b][font=宋体][size=9pt]不会安装默认路由！[/size][/font][/b][b][size=9pt][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman]
35.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[font=Times New Roman][b][size=9pt]C
35.1.1.0 is directly connected, Serial1/0[/size][/b][size=9pt][/size][/font]
[b][size=9pt][font=Times New Roman]
3.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]i L1
3.3.3.0 [115/20] via 35.1.1.3, Serial1/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
4.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]i L1
4.4.4.0 [115/20] via 45.1.1.4, Serial2/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
5.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]C
5.5.5.0 is directly connected, Loopback0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
24.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]i L1
24.1.1.0 [115/20] via 45.1.1.4, Serial2/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
10.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]i L1
10.1.1.0 [115/20] via 35.1.1.3, Serial1/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
[115/20] via 45.1.1.4, Serial2/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
13.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]i L1
13.1.1.0 [115/20] via 35.1.1.3, Serial1/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
45.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]C
45.1.1.0 is directly connected, Serial2/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R3[/font][/size][/b][b][font=宋体][size=9pt]和[/size][/font][/b][b][size=9pt][font=Times New Roman]R4[/font][/size][/b][b][font=宋体][size=9pt]的数据库中[/size][/font][/b][b][size=9pt][font=Times New Roman]ATT[/font][/size][/b][b][font=宋体][size=9pt]数值时[/size][/font][/b][b][size=9pt][font=Times New Roman]0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R3#sho isis dat [/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman]IS-IS Level-1 Link State Database:[/font][/size][/b]
[b][size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size][/b]
[font=Times New Roman][b][size=9pt]R3.00-00
* 0x00000016
0xD269
756
[/size][/b][size=9pt]
0/[/size][b][size=9pt]0/0[/size][/b][/font]
[font=Times New Roman][b][size=9pt]R4.00-00
0x00000018
0x918A
1084
[/size][/b][size=9pt]
0/[/size][b][size=9pt]0/0[/size][/b][/font]
[b][size=9pt][font=Times New Roman]R4.01-00
0x0000000B
0xA898
1028
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R5.00-00
0x00000013
0x882D
983
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]IS-IS Level-2 Link State Database:[/font][/size][/b]
[b][size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R1.00-00
0x0000000F
0x39DB
780
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R2.00-00
0x0000000F
0xD42C
806
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R3.00-00
* 0x0000001A
0x82CE
921
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4.00-00
0x0000001B
0xFD4B
943
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4.01-00
0x00000009
0x3C8F
428
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4#sho isi dat[/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman]IS-IS Level-1 Link State Database:[/font][/size][/b]
[b][size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R3.00-00
0x0000000E
0xE261
1197
[color=red]
0[/color]/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4.00-00
* 0x00000010
0xA182
1199
[color=red]
0[/color]/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4.01-00
* 0x00000003
0xB890
1192
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R5.00-00
0x0000000B
0x9825
1193
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]IS-IS Level-2 Link State Database:[/font][/size][/b]
[b][size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R1.00-00
0x00000007
0x49D3
1131
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R2.00-00
0x00000007
0xE424
1192
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R3.00-00
0x00000011
0x447F
1193
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4.00-00
* 0x00000012
0xA282
1195
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4.01-00
* 0x00000002
0x4A88
1192
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R5.00-00
0x00000006
0x2D20
785
0/0/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][font=宋体][size=9pt]然后，我们把[/size][/font][/b][b][size=9pt][font=Times New Roman]R1[/font][/size][/b][b][font=宋体][size=9pt]和[/size][/font][/b][b][size=9pt][font=Times New Roman]R2[/font][/size][/b][b][font=宋体][size=9pt]的区域数值改成[/size][/font][/b][b][size=9pt][font=Times New Roman]47[/font][/size][/b][b][font=宋体][size=9pt]。[/size][/font][/b][b][size=9pt][font=Times New Roman]0001[/font][/size][/b]
[b][font=宋体][size=9pt]把[/size][/font][/b][b][size=9pt][font=Times New Roman]R3[/font][/size][/b][b][font=宋体][size=9pt]和[/size][/font][/b][b][size=9pt][font=Times New Roman]R4[/font][/size][/b][b][font=宋体][size=9pt]的区域数值改成[/size][/font][/b][b][size=9pt][font=Times New Roman] 48[/font][/size][/b][b][font=宋体][size=9pt]。[/size][/font][/b][b][size=9pt][font=Times New Roman]0001[/font][/size][/b]
[b][font=宋体][size=9pt]把[/size][/font][/b][b][size=9pt][font=Times New Roman]R5[/font][/size][/b][b][font=宋体][size=9pt]的区域数值改成[/size][/font][/b][b][size=9pt][font=Times New Roman]47[/font][/size][/b][b][font=宋体][size=9pt]。[/size][/font][/b][b][size=9pt][font=Times New Roman]0001[/font][/size][/b]
[b][font=宋体][size=9pt]这时[/size][/font][/b][b][size=9pt][font=Times New Roman]R5[/font][/size][/b][b][font=宋体][size=9pt]和其他的路由器失去了邻居关系[/size][/font][/b][b][size=9pt][/size][/b]
[b][size=9pt][font=Times New Roman]
35.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]C
35.1.1.0 is directly connected, Serial1/0[/font][/size][/b]
[b][size=9pt][font=Times New Roman]
5.0.0.0/24 is subnetted, 1 subnets[/font][/size][/b]
[b][size=9pt][font=Times New Roman]C
5.5.5.0 is directly connected, Loopback0[/font][/size][/b]
[font=Times New Roman][b][size=9pt]
[/size][/b][b][size=9pt]45.0.0.0/24 is subnetted, 1 subnets[/size][/b][/font]
[b][size=9pt][font=Times New Roman]C
45.1.1.0 is directly connected, Serial2/0[/font][/size][/b]
[b][font=宋体][size=9pt]问题出来了，[/size][/font][/b][b][size=9pt][font=Times New Roman]R3[/font][/size][/b][b][font=宋体][size=9pt]和[/size][/font][/b][b][size=9pt][font=Times New Roman]R4[/font][/size][/b][b][font=宋体][size=9pt]的数据库里会显示：[/size][/font][/b][b][size=9pt][/size][/b]
[b][size=9pt][font=Times New Roman]R3#sho isis dat[/font][/size][/b]
[size=9pt][font=Times New Roman]IS-IS Level-1 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
* 0x00000054
0xEC49
1197
[b][color=red]
1[/color][/b]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
0x00000057
0x745E
1030
[b][color=red]
1[/color][/b]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.02-00
0x00000005
0xAD98
1028
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x0000003D
0x6133
1029
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]IS-IS Level-2 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R1.00-00
0x0000005A
0xD8B0
1198
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R2.00-00
0x00000044
0xBF3F
1028
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
* 0x0000006F
0x4006
1194
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
0x00000069
0xAC05
1195
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.02-00
0x0000001C
0x1614
1028
0/0/0[/font][/size]
[b][size=9pt][font=Times New Roman]R4#sho isis dat [/font][/size][/b]
[size=9pt][font=Times New Roman] [/font][/size]
[size=9pt][font=Times New Roman]IS-IS Level-1 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
0x00000006
0xFF43
1068
[b][color=red]
1[/color][/b]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
* 0x00000009
0xBC65
1075
[b][color=red]
1[/color][/b]/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.01-00
* 0x00000001
0xBC8E
921
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x00000007
0xA51B
1071
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]IS-IS Level-2 Link State Database:[/font][/size]
[size=9pt][font=Times New Roman]LSPID
LSP Seq Num
LSP Checksum
LSP Holdtime
ATT/P/OL[/font][/size]
[size=9pt][font=Times New Roman]R1.00-00
0x00000005
0x4DD1
860
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R2.00-00
0x00000005
0xE822
911
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R3.00-00
0x00000009
0x7DE3
1069
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.00-00
* 0x0000000C
0x2136
1081
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R4.01-00
* 0x00000001
0x4C87
921
0/0/0[/font][/size]
[size=9pt][font=Times New Roman]R5.00-00
0x00000006
0x2D20
989
0/0/0[/font][/size]
[size=9pt][font=Times New Roman] [/font][/size]
[b][font=宋体][size=9pt]大家看到了吗？这时[/size][/font][/b][b][size=9pt][font=Times New Roman]R3[/font][/size][/b][b][font=宋体][size=9pt]和[/size][/font][/b][b][size=9pt][font=Times New Roman]R4[/font][/size][/b][b][font=宋体][size=9pt]的数据库中还时会显示[/size][/font][/b][b][size=9pt][font=Times New Roman]Level-1 Link State [/font][/size][/b][b][font=宋体][size=9pt]的[/size][/font][/b][b][size=9pt][font=Times New Roman]ATT[/font][/size][/b][b][font=宋体][size=9pt]数值为[/size][/font][/b][b][size=9pt][font=Times New Roman]1[/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman] [/font][/size][/b]
[b][size=9pt][font=Times New Roman]R5#sho clns nei[/font][/size][/b]
[b][size=9pt][font=Times New Roman]System Id
Interface
SNPA
State
Holdtime
Type Protocol[/font][/size][/b]
[b][size=9pt][font=Times New Roman]R4
Se2/0
*HDLC*
Up
275
IS
[color=red]ES-IS[/color][/font][/size][/b]
[b][size=9pt][font=Times New Roman]R3
Se1/0
*HDLC*
Up
255
IS
[color=red]
ES-IS[/color][/font][/size][/b]
[size=3][b][color=blue][size=10.5pt][font=Times New Roman]R5[/font][/size][/color][/b][b][color=blue][font=宋体]和[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R3[/font][/size][/color][/b][b][color=blue][font=宋体]、[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R4[/font][/size][/color][/b][b][color=blue][font=宋体]的邻居关系变成了[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]ES-IS[/font][/size][/color][/b][b][color=blue][font=宋体]的关系，[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R5[/font][/size][/color][/b][b][color=blue][font=宋体]相当于一个终端的[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]PC[/font][/size][/color][/b][b][color=blue][font=宋体]，那么为什么[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R3[/font][/size][/color][/b][b][color=blue][font=宋体]和[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R4[/font][/size][/color][/b][b][color=blue][font=宋体]还要发送[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]LEVEL 1[/font][/size][/color][/b][b][color=blue][font=宋体]的[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]LSP[/font][/size][/color][/b][b][color=blue][font=宋体]包呢？发送的作用时什么？发送的[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]LSP[/font][/size][/color][/b][b][color=blue][font=宋体]包发到了何处？是用来保持邻居关系的建立的吗？[/font][/color][/b][b][color=blue][size=10.5pt][/size][/color][/b][/size]
[size=3][b][color=blue][font=宋体]如果按照文章前的那段话理解这个[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]ATT[/font][/size][/color][/b][b][color=blue][font=宋体]值，就是[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]L1/L2[/font][/size][/color][/b][b][color=blue][font=宋体]的路由器，发送[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]L1 LSP[/font][/size][/color][/b][b][color=blue][font=宋体]，当[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]L1[/font][/size][/color][/b][b][color=blue][font=宋体]的路由器收到这个[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]LSP[/font][/size][/color][/b][b][color=blue][font=宋体]包的时候，就会添加一条默认路由，以此达到与[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]L2[/font][/size][/color][/b][b][color=blue][font=宋体]路由器互相通信的目的！[/font][/color][/b][b][color=blue][size=10.5pt][/size][/color][/b][/size]
[size=3][b][color=red][font=宋体]主要的目的就时让[/font][/color][/b][b][color=red][size=10.5pt][font=Times New Roman]L1[/font][/size][/color][/b][b][color=red][font=宋体]的路由器添加一条默认路由！！[/font][/color][/b][b][color=red][size=10.5pt][/size][/color][/b][/size]
[size=3][b][color=blue][font=宋体]但是，以上实验[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R3[/font][/size][/color][/b][b][color=blue][font=宋体]和[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R4[/font][/size][/color][/b][b][color=blue][font=宋体]发送[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]LSP[/font][/size][/color][/b][b][color=blue][font=宋体]包，[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]R5[/font][/size][/color][/b][b][color=blue][font=宋体]并不可能安装默认路由，那发送[/font][/color][/b][b][color=blue][size=10.5pt][font=Times New Roman]L1 LSP[/font][/size][/color][/b][b][color=blue][font=宋体]的目的是什么？[/font][/color][/b][/size]
