拓扑图

IP-IS_IS OL与COST_路由表

配置

sysname AR1
#
isis 1
 is-level level-2
 network-entity 49.0000.0000.0001.00
#
interface GigabitEthernet0/0/0
 ip address 12.1.1.1 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 13.1.1.1 255.255.255.0 
 isis enable 1
#
interface LoopBack0
 ip address 1.1.1.1 255.255.255.255 
 isis enable 1
#
sysname AR2
#
isis 1
 is-level level-2
 network-entity 49.0000.0000.0002.00
#
interface GigabitEthernet0/0/0
 ip address 12.1.1.2 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 23.1.1.2 255.255.255.0 
 isis enable 1
#
interface LoopBack0
 ip address 2.2.2.2 255.255.255.255 
 isis enable 1
#
sysname AR3
#
isis 1
 is-level level-2
 network-entity 49.0000.0000.0003.00
#
interface GigabitEthernet0/0/0
 ip address 13.1.1.3 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 23.1.1.3 255.255.255.0 
 isis enable 1
#
interface LoopBack0
 ip address 3.3.3.3 255.255.255.255 
 isis enable 1
#

通过修改cost影响选路

查看AR2的路由表

去往3.3.3.3走AR3

IP-IS_IS OL与COST_路由表_02

修改AR2的G0/0/1接口cost为21（默认接口cost为10）

interface GigabitEthernet0/0/1
 isis cost 21
#

查看去往3.3.3.3的路由，下一跳为AR1

IP-IS_IS OL与COST_路由表_03

设置OL位

在AR1上设置OL位，使AR2去往3.3.3.3不走AR1

isis 1
 set-overload
#

查看AR2的路由表，去往3.3.3.3，下一跳为AR3

IP-IS_IS OL与COST_路由表_04

AR1通告的LSP的OL位置1

IP-IS_IS OL与COST_路由表_05