1.VRRP技术
虚拟路由冗余协议(Virtual Router Redundancy Protocol,简称VRRP),是一个IP协议族,我们知道IP协议族里面有ICMP、OSPF,VRRP也是IP协议族的一员,协议号为112。在VRRP里面,设备有两种角色Master,Backup),其中Master负责跑业务流量,而Backup负责备份,当Master挂掉之后,Backup自动抢占为Master,然后所有的数据从Master上走 。VRRP主要是用来做出口链路的冗余备份的,可以有多个网关设备加入一个备份组,但是只能有一个Master设备,当Master设备挂掉之后,其他的Backup设备自动抢占为Master设备,保障网络的可靠性。
2.VRRP配置实例
要求:
SW1为vlan10的主网关,vlan20的备份网关
SW2为vlan20的主网关,vlan10的备份网关
配置参数
VLAN10
SW1配置
interface Vlan10
ip address 10.10.10.3 255.255.255.0
vrrp 1 ip 10.10.10.1
vrrp 1 preempt delay minimum 5
vrrp 1 priority 120
vrrp 1 track 1 decrement 20
!
SW2配置
interface Vlan10
ip address 10.10.10.4 255.255.255.0
vrrp 1 ip 10.10.10.1
vrrp 1 preempt delay minimum 5
vrrp 1 priority 150
!
VLAN20
SW1配置
interface Vlan20
ip address 10.10.20.3 255.255.255.0
vrrp 2 ip 10.10.20.1
vrrp 2 preempt delay minimum 5
!
SW2配置
track 2 interface Ethernet0/2 line-protocol //追踪上联端口
interface Vlan20
ip address 10.10.20.4 255.255.255.0
vrrp 2 ip 10.10.20.1
vrrp 2 preempt delay minimum 5
vrrp 2 priority 120
vrrp 2 track 2 decrement 40
!
结果测试:
在SW1上查看
Switch#show vrrp
Vlan10 - Group 1
State is Backup
Virtual IP address is 10.10.10.1
Virtual MAC address is 0000.5e00.0101
Advertisement interval is 1.000 sec
Preemption enabled, delay min 5 secs
Priority is 120
Track object 1 state Up decrement 20
Master Router is 10.10.10.4, priority is 150
Master Advertisement interval is 1.000 sec
Master Down interval is 3.531 sec (expires in 3.431 sec)
Vlan20 - Group 2
State is Backup
Virtual IP address is 10.10.20.1
Virtual MAC address is 0000.5e00.0102
Advertisement interval is 1.000 sec
Preemption enabled, delay min 5 secs
Priority is 100
Master Router is 10.10.20.4, priority is 120
Master Advertisement interval is 1.000 sec
Master Down interval is 3.609 sec (expires in 2.994 sec)
在SW2上查看
Switch#show vrrp
Vlan10 - Group 1
State is Master
Virtual IP address is 10.10.10.1
Virtual MAC address is 0000.5e00.0101
Advertisement interval is 1.000 sec
Preemption enabled, delay min 5 secs
Priority is 150
Master Router is 10.10.10.4 (local), priority is 150
Master Advertisement interval is 1.000 sec
Master Down interval is 3.414 sec
Vlan20 - Group 2
State is Master
Virtual IP address is 10.10.20.1
Virtual MAC address is 0000.5e00.0102
Advertisement interval is 1.000 sec
Preemption enabled, delay min 5 secs
Priority is 120
Track object 2 state Up decrement 40
Master Router is 10.10.20.4 (local), priority is 120
Master Advertisement interval is 1.000 sec
Master Down interval is 3.531 sec
追踪测试:
关闭SW2的上联端口e0/2
SW1切换为VLAN20的主网关
Switch(config)#int e 0/2
Switch(config-if)#sh
Switch(config-if)#
*Nov 11 06:13:48.928: %TRACK-6-STATE: 2 interface Et0/2 line-protocol Up -> Down
Switch(config-if)#
*Nov 11 06:13:50.933: %LINK-5-CHANGED: Interface Ethernet0/2, changed state to administratively down
*Nov 11 06:13:51.935: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/2, changed state to down
Switch(config-if)#
*Nov 11 06:13:54.461: %VRRP-6-STATECHANGE: Vl20 Grp 2 state Master -> Backup
SW2开启上联端口e0/2
SW2恢复为VLAN20的主网关
Switch(config-if)#no sh
Switch(config-if)#
*Nov 11 06:14:05.361: %LINK-3-UPDOWN: Interface Ethernet0/2, changed state to up
Switch(config-if)#
*Nov 11 06:14:06.699: %TRACK-6-STATE: 2 interface Et0/2 line-protocol Down -> Up
Switch(config-if)#
*Nov 11 06:14:07.373: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/2, changed state to up
Switch(config-if)#
*Nov 11 06:14:12.035: %VRRP-6-STATECHANGE: Vl20 Grp 2 state Backup -> Master