在思科设备上配置VRRP MSTP实现网关冗余和负载分担

拓扑如下图所示：

具体配置如下：

SW3： 先创建vlan10,20 vlan 10 vlan 20 然后在接口下划分trunk、access模式 interface Ethernet0/3 switchport mode access switchport access vlan 10 interface Ethernet1/0 switchport mode access switchport access vlan 20 int range e0/1 , e0/2 switchport trunk encapsulation dot1q switchport mode trunk switchport trunk allowed vlan 10,20 配置mstp spanning-tree mode mstp spanning-tree mst configuration name qgtest revision 123 instance 10 vlan 10 instance 20 vlan 20 SW1： 先创建vlan10,20 vlan 10 vlan 20 配置链路聚合和trunk口 interface range e0/2 , e0/0 , e0/1 switchport trunk encapsulation dot1q switchport mode trunk switchport trunk allowed vlan 10,20 interface range e0/2 , e0/0 channel-group 1 mode on 配置mstp spanning-tree mode mstp spanning-tree mst configuration name qgtest revision 123 instance 10 vlan 10 instance 20 vlan 20 spanning-tree mst 10 root primary spanning-tree mst 20 root sec 配置vrrp interface Vlan10 ip address 192.168.10.253 255.255.255.0 vrrp 10 ip 192.168.10.254 vrrp 10 priority 200 interface Vlan20 ip address 192.168.20.252 255.255.255.0 vrrp 20 ip 192.168.20.254 vrrp 20 priority 100 SW2： 先创建vlan10,20 vlan 10 vlan 20 配置链路聚合和trunk口 interface range e0/2 , e0/0 , e0/1 switchport trunk encapsulation dot1q switchport mode trunk switchport trunk allowed vlan 10,20 interface range e0/2 , e0/0 channel-group 1 mode on 配置mstp spanning-tree mode mstp spanning-tree mst configuration name qgtest revision 123 instance 10 vlan 10 instance 20 vlan 20 spanning-tree mst 20 root primary spanning-tree mst 10 root sec 配置vrrp interface Vlan20 ip address 192.168.20.253 255.255.255.0 vrrp 20 ip 192.168.20.254 vrrp 20 priority 200 interface Vlan10 ip address 192.168.10.252 255.255.255.0 vrrp 10 ip 192.168.10.254 vrrp 10 priority 100

备注：如果SW1有上行接口和上行链路时，其中一个发生故障，VRRP默认是无法感知的，即主备状态无法切换，数据包无法发送出去，这是就要用到track功能。具体配置如下：

SW1/SW2： vrrp 10 track 1 decrement 150 track 1 int g0/0/3 line-protocol 假设G0/0/3为上行口，配置完这条命令之后，即当上行链路发生故障时，其优先级减少150,然后当前优先级小于Backup状态的三层交换机，则主备状态发生切换。