单臂路由
概念:如图大纲LSW1是二层交换机不具备三层路由功能,并且连接着不同的vlan,并使每个vlan都可以与外网通信,那么就要用单臂路由技术,原理是将图中的AR1的ge0/0/0接口逻辑上分为多个子接口,分别对应不同的vlan的网关。

LSW1配置:
vlan batch 10 20
interface GigabitEthernet0/0/1
port link-type trunk
port trunk allow-pass vlan 10 20
#
interface GigabitEthernet0/0/2
port link-type access
port default vlan 10
#
interface GigabitEthernet0/0/3
port link-type access
port default vlan 20
AR1配置
interface GigabitEthernet0/0/0.10
dot1q termination vid 10 //将子接口作为vlan 10的网关
ip address 192.168.1.1 255.255.255.0
arp broadcast enable //启用arp广播功能,不启用vlan间无法通信
#
interface GigabitEthernet0/0/0.20
dot1q termination vid 20
ip address 192.168.2.1 255.255.255.0
arp broadcast enable
效果:从pc1中tracert 192.168.2.2

策略路由
原理:使用基于原地址或者目标地址策略转发数据到下一个接口,策略路由不会影响路由表,案例如图所示
全局启用ospf协议,正常情况下pc1访问pc2路径为pc1--->AR1--->AR3--->pc2,先通过在AR1上通过策略路由将路径改为pc1--->AR1--->AR2--->AR3--->pc2
无论是使用策略路由前,还是之后,AR1路由表中去往192.168.2.0/24,都是下图:

拓扑图

AR1不配置策略路由时 pc1 tracert 192.168.2.2

AR1配置策略路由时 pc1 tracert 192.168.2.2

AR1配置:
interface GigabitEthernet0/0/0
ip address 13.1.1.1 255.255.255.0
#
interface GigabitEthernet0/0/1
ip address 12.1.1.1 255.255.255.0
#
interface GigabitEthernet0/0/2
ip address 192.168.1.1 255.255.255.0
ospf 1 router-id 1.1.1.1
area 0.0.0.0
network 12.1.1.0 0.0.0.255
network 13.1.1.0 0.0.0.255
network 192.168.1.0 0.0.0.255
以下策略路由:
抓取流量:
acl number 3000
rule 5 permit ip source 192.168.1.0 0.0.0.255 destination 192.168.2.0 0.0.0.255
定义流分类:
traffic classifier dingxiang operator or
if-match acl 3000
定义流行为:
traffic behavior bdingxing
redirect ip-nexthop 12.1.1.2
定义流策略
traffic policy pdingxiang
classifier dingxiang behavior bdingxing
在接口启用策略:
interface GigabitEthernet0/0/2
ip address 192.168.1.1 255.255.255.0
traffic-policy pdingxiang inbound
AR2配置:
interface GigabitEthernet0/0/0
ip address 12.1.1.2 255.255.255.0
#
interface GigabitEthernet0/0/1
ip address 23.1.1.1 255.255.255.0
ospf 1 router-id 2.2.2.2
area 0.0.0.0
network 12.1.1.0 0.0.0.255
network 23.1.1.0 0.0.0.255
AR3配置:
interface GigabitEthernet0/0/0
ip address 13.1.1.2 255.255.255.0
#
interface GigabitEthernet0/0/1
ip address 23.1.1.2 255.255.255.0
#
interface GigabitEthernet0/0/2
ip address 192.168.2.1 255.255.255.0
ospf 1 router-id 3.3.3.3
area 0.0.0.0
network 13.1.1.0 0.0.0.255
network 23.1.1.0 0.0.0.255
network 192.168.2.0 0.0.0.255