ISIS路由渗透实验

news2024/11/24 12:26:33

1）拓扑

2）需求：ISIS全网互联互通

3）原因分析：

因为，L1/2 路由器（R4、R8）学习到L1类型路由信息会装进L2-LSP，在泛洪给其他区域的L2和L1/2路由器，所以，L1/2路由器和L2路由器能够清晰的掌握全网的路由信息（所以骨干区域的路由器能掌握全网的明细路由）

-但是，为了有效减小L1邻居（R6）路由表的规模，默认情况下，L1/2路由器（R4、R8）不会将其他区域的路由信息通报给自己所在L1区域，所以L1路由器（R6）根本不了解本区域以外的路由信息，所以会导致L1路由器（R6）访问其他区域网络时无法选择最优的路由

-当L1区域里面去往L2区域有两个或者两个以上的L1/2,就有可能会产生次优路径，就有可能导致本实验中R6不能选择最好的路由

-如何解决这个问题，在R4 和R8上做路由渗透，将L2区域的路由信息渗透到L1区域，实现R6路由器自己计算最优的路由

备注：R8-不要忘记修改cost的类型

[R8]isis 1

[R8-isis-1]cost-style wide

4）配置命令
sysname R6
#
isis 1
is-level level-1
network-entity 49.0010.0000.0000.0006.00
#
interface GigabitEthernet0/0/0
ip address 192.168.46.6 255.255.255.0
isis enable 1
isis cost 15 //修改cost值
#
interface GigabitEthernet0/0/1
ip address 192.168.68.6 255.255.255.0
isis enable 1

sysname R4
#
isis 1
network-entity 49.0010.0000.0000.0004.00
import-route isis level-2 into level-1 //将L2区域中的路由信息渗透到L1区域
#
interface GigabitEthernet0/0/0
ip address 192.168.14.4 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/1
ip address 192.168.46.4 255.255.255.0
isis enable 1

sysname R1
#
isis 1
is-level level-2
network-entity 49.0020.0000.0000.0001.00
#
interface GigabitEthernet0/0/0
ip address 192.168.12.1 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/1
ip address 192.168.14.1 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/2
ip address 192.168.81.1 255.255.255.0
isis enable 1

sysname R2
#
isis 1
is-level level-2
network-entity 49.0020.0000.0000.0002.00
#
interface GigabitEthernet0/0/0
ip address 192.168.12.2 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/1
ip address 192.168.23.2 255.255.255.0
isis enable 1

sysname R3
#
isis 1
is-level level-2
network-entity 49.0020.0000.0000.0003.00
#
interface GigabitEthernet0/0/0
ip address 192.168.23.3 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/1
ip address 192.168.35.3 255.255.255.0
isis enable 1

sysname R5
#
isis 1
network-entity 49.0030.0000.0000.0005.00
#
interface GigabitEthernet0/0/0
ip address 192.168.35.5 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/1
ip address 192.168.57.5 255.255.255.0
isis enable 1

sysname R7
#
isis 1
is-level level-1
network-entity 49.0030.0000.0000.0007.00
#
interface GigabitEthernet0/0/0
ip address 192.168.57.7 255.255.255.0
isis enable 1
#
interface LoopBack0
ip address 192.168.2.1 255.255.255.0
isis enable 1

sysname R8
#
isis 1
network-entity 49.0010.0000.0000.0008.00
import-route isis level-2 into level-1 //将L2区域中的路由信息渗透到L1区域
#
interface GigabitEthernet0/0/0
ip address 192.168.68.8 255.255.255.0
isis enable 1
#
interface GigabitEthernet0/0/1
ip address 192.168.81.8 255.255.255.0
isis enable 1
isis cost 55 level-2 //配置接口去往level-2区域的开销值为55