CISCO设备VRRP+MSTP快速配置（思科vrrp路由配置命令详细解释）

虚拟路由冗余协议(Virtual Router Redundancy Protocol，简称VRRP)，是一个公有协议族，协议号为112。在VRRP里面，设备有两种角色Master,Backup，其中Master是主，Backup是备份，当Master挂掉之后，Backup自动抢占为Master，然后所有的数据转发随之切换 。

VRRP的作用和HSRP非常相似，用来做网关冗余，可以和MSTP（多实例生成树）结合使用，使内网设备达到负载冗余的效果。

拓扑说明：

RT作为出口路由器，配置loo 0 模拟互联网

SW1SW2核心层交换，SW1作为VL10主根 VL20的次根，SW2作为VL20主根 VL10的次根

配置VRRP，SW1作为VL10的默认网关VL20 的备份网关，SW2作为VL20的默认网关VL10 的备份网关。

核心设备一旦故障，自动倒换到对侧。

PC1 192.168.10.1/24

PC2 192.168.20.1/24

配置方法:

RT配置

hostname RT

interface Loopback0

ip address 1.1.1.1 255.255.255.255

interface GigabitEthernet0/1

ip address 10.0.0.2 255.255.255.0

interface GigabitEthernet0/2

ip address 20.0.0.2 255.255.255.0

//配置接口IP地址

ip route 0.0.0.0 0.0.0.0 Loopback0

//配置默认路由

router ospf 110

router-id 1.1.1.1

network 10.0.0.2 0.0.0.0 area 0

network 20.0.0.2 0.0.0.0 area 0

default-information originate

//配置OSPF，下发默认路由

SW1配置

hostname SW1

vlan 10

vlan 20

vlan 100

spanning-tree mode mst

spanning-tree mst configuration

name cisco

revision 12

instance 10 vlan 10

instance 20 vlan 20

exit

spanning-tree mst 10 root primary

spanning-tree mst 20 root secondary

//配置MSTP，建立两个实例对应VL10 VL20

interface GigabitEthernet0/0

switchport access vlan 100

switchport mode access

interface GigabitEthernet0/1

switchport trunk encapsulation dot1q

switchport mode trunk

interface GigabitEthernet0/2

switchport trunk encapsulation dot1q

switchport mode trunk

interface GigabitEthernet0/3

switchport trunk encapsulation dot1q

switchport mode trunk

//接口放行所有VLAN

interface Vlan10

ip address 192.168.10.252 255.255.255.0

vrrp 1 ip 192.168.10.254

vrrp 1 priority 120

//配置VL10地址，VRRP虚拟网关地址，优先级120为主（默认100），默认抢占开启

interface Vlan20

ip address 192.168.20.252 255.255.255.0

vrrp 2 ip 192.168.20.254

//配置VL20地址，VRRP虚拟网关地址

interface Vlan100

ip address 10.0.0.1 255.255.255.0

//配置出口互联地址

router ospf 110

router-id 10.0.0.1

passive-interface Vlan10

passive-interface Vlan20

network 10.0.0.1 0.0.0.0 area 0

network 192.168.10.252 0.0.0.0 area 0

network 192.168.20.252 0.0.0.0 area 0

//配置OSPF宣告各网段，内网VLAN被动模式，减少LSA泛洪

SW2 配置

hostname SW2

vlan 10

vlan 20

vlan 100

spanning-tree mode mst

spanning-tree mst configuration

name cisco

revision 12

instance 10 vlan 10

instance 20 vlan 20

exit

spanning-tree mst 10 root secondary

spanning-tree mst 20 root primary

interface GigabitEthernet0/0

switchport access vlan 200

switchport mode access

interface GigabitEthernet0/1

switchport trunk encapsulation dot1q

switchport mode trunk

interface GigabitEthernet0/2

switchport trunk encapsulation dot1q

switchport mode trunk

interface GigabitEthernet0/3

switchport trunk encapsulation dot1q

switchport mode trunk

interface Vlan10

ip address 192.168.10.253 255.255.255.0

vrrp 1 ip 192.168.10.254

interface Vlan20

ip address 192.168.20.253 255.255.255.0

vrrp 2 ip 192.168.20.254

vrrp 2 preempt delay minimum 1

vrrp 2 priority 120

interface Vlan200

ip address 20.0.0.1 255.255.255.0

router ospf 110

router-id 20.0.0.1

passive-interface Vlan10

passive-interface Vlan20

network 20.0.0.1 0.0.0.0 area 0

network 192.168.10.253 0.0.0.0 area 0

network 192.168.20.253 0.0.0.0 area 0

SW3 SW4配置

hostname SW3

vlan 10

vlan 20

spanning-tree mode mst

spanning-tree mst configuration

name cisco

revision 12

instance 10 vlan 10

instance 20 vlan 20

exit

interface GigabitEthernet0/0

switchport access vlan 10

// SW4此处配置为switchport access vlan 20

switchport mode access

interface GigabitEthernet0/1

switchport trunk encapsulation dot1q

switchport mode trunk

interface GigabitEthernet0/2

switchport trunk encapsulation dot1q

switchport mode trunk

配置完成后检查

SW1#show spanning-tree

SW1#show vrrp

SW2#show spanning-tree

SW2#show vrrp

PC1 PC2 分别走两侧访问外网

将SW1关闭，在SW2观察状态，MSTP 实例10 VRRP 1 状态随之切换

SW2#show spanning-tree

SW2#show vrrp

PC1访问外网随之切换到对侧

将SW2设备关闭，VL20 VRRP2 倒换现象与此一致。