拓扑图

配置

nexthop weight影响路由加入路由表

weight默认为255，取值1~255，值越小越优先

sysname R1
#
isis 1
 is-level level-1
 cost-style wide
 network-entity 49.1234.0000.0000.0001.00
 log-peer-change topology
#
interface GigabitEthernet0/0/0
 ip address 10.1.12.1 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 10.1.13.1 255.255.255.0 
 isis enable 1
#

sysname R2
#
isis 1
 cost-style wide
 network-entity 49.1234.0000.0000.0002.00
#
interface GigabitEthernet0/0/0
 ip address 10.1.12.2 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 10.1.24.2 255.255.255.0 
 isis enable 1
#

sysname R3
#
isis 1
 cost-style wide
 network-entity 49.1234.0000.0000.0003.00
#
interface GigabitEthernet0/0/0
 ip address 10.1.13.3 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 10.1.34.3 255.255.255.0 
 isis enable 1
#

sysname R4
#
isis 1
 is-level level-2
 cost-style wide
 network-entity 49.1234.0000.0000.0004.00
 network-entity 49.0000.0000.0000.0004.00
#
interface GigabitEthernet0/0/0
 ip address 10.1.24.4 255.255.255.0 
 isis enable 1
#
interface GigabitEthernet0/0/1
 ip address 10.1.34.4 255.255.255.0 
 isis enable 1
#
interface LoopBack0
 ip address 4.4.4.4 255.255.255.0 
 isis enable 1
#

查看结果

查看R1的路由表

查看isis数据库

R1通过边界下发的ATT置1的LSP，生成2条默认路由，两条默认路由负载均衡

通过修改weight值，使其中下一跳为R2的路由加表

isis 
 nexthop 10.1.12.2 weight 1
#

再次查看路由表，只有一条下一跳为10.1.12.2的路由存在