VRRP概述及其简单配置
vrrp概述：
1.Virtual Router Redundancy Protocol，也即虚拟路由器冗余协议。
2.利用VRRP，一组路由器(同一个LAN中的接口)协同工作，但只有一个处于Master状态， 处于该状态的路由器（的接口）承担实际的数据流量转发任务。在一个VRRP组内的多 个路由器接口共用一个虚拟IP地址，该地址被作为局域网内所有主机的缺省网关地址。
3.VRRP决定哪个路由器是Master , Master路由器负责接收发送至用户网关的数据包并进 行转发，以及响应PC对于其网关IP地址的ARP请求。
4.Backup路由器侦听Master路由器的状态，并在Master路由器发生故障时，接替其工 作，从而保证业务流量的平滑切换。
VRRP术语
VRRP路由器:
运行VRRP的路由器。一台VRRP路由器(的接口)可以同时参与到多个VRRP组中，在不同的组中，一台VRRP路由器可以充当不同的角色。
VRRP组:
一个VRRP组由多个VRRP路由器组成，使用相同的VRID ( Virtual Router lD ,虚拟路由器ID) 进行标识，属于同一VRRP组的VRRP路由器互相交换信息，每一个VRRP组中只能有一个Master.
虚拟路由器:
对于每一个VRRP组，抽象出来的一个逻辑路由器，该路由器充当网络用户的网关，该路由器并非真实存在，事实上对于用户而言，只需知道虚拟路由器的IP，至于具体的虚拟路由器的角色由谁来承担、数据转发任务由谁来承担、Master故障后谁来接替，这是VRRP的工作。
虚拟IP地址、MAC地址:
1.虚拟IP地址就是虚拟路由器的IP地址，该地址实际上就是用户的网关地址。
2.虚拟MAC地址是虚拟路由器根据VRID生成的MAC地址。一个虚拟路由器拥有一个虚拟 MAC地址，格式为:00-00-5E-0O-O1-fVRID}。
Master&Backup路由器：
Master路由器:在VRRP组中实际转发数据包的路由器，在每一个VRRP组中，仅有Master响应对虚拟IP地址的ARP请求。Master路由器同时以一定的时间间隔发送VRRP消息，以便通知Backup路由器自己的存活情况。
1.以虚拟MAC地址响应其他设备对虚拟IP地址的ARP请求。
2.转发目的MAC地址为虚拟MAC地址的IP报文。
3.如果它是这个虚拟IP地址的拥有者(接口实际P地址为虚拟IP地址），则接收目的IP地址为这个虚拟IP地址的IP报文。否则，丢弃这个IP报文。
4.如果收到比自己优先级大的报文，立即成为Backup。
5.如果收到与自己优先级相等的VRRP报文且本地接口IP地址小于对端接口IP，立即成为Backup。
Backup路由器:处于监听状态的路由器，一旦Master路由器出现故障，Backup路由器就开始接替工作。
1.对虚拟IP地址的ARP请求，不做响应。
2.丢弃目的IP地址为虚拟IP地址的IP报文。
3.如果收到优先级和自己相同或者比自己大的报文，则重置Master_Down_Interval定时器，不进一步比较IP地址。
4.如果收到比自己优先级小的报文且该报文优先级是0时，定时器时间设置为Skew_time(偏移时间)，如果该报文优先级不是0，丢弃报文，立刻成为Master。
选举依据:先比较接口VRRP优先级(比大），如果相等，则比较接口IP地址（比大)。
VRRP状态机
VRRP协议的状态共有三种，分别是Initialize,Master ，Backup，初始状态都是lnitialize，通过比较优先级产生Master和Backup，在规定时间内，Backup若没有收到Master发来的心跳报文，将切换为Master。
VRRP的工作过程
1. VRRP组中的设备选举出Master. Master设备通过发送免费ARP报文,将虚拟MAC地址通 知给与它连接的设备或者主机,从而承担报文转发任务。
2. Master设备周期性向备份组内所有Backup设备发送VRRP通告报文。
3.如果Master设备出现故障 , VRRP备份组中的Backup设备重新选举新的Master.
4. VRRP组状态切换时, Master设备由一台设备切换为另外-台设备,新的Master设备会立即 发送携带虚拟路由器的虚拟MAC地址和虚拟IP地址信息的免费ARP报文,刷新与它连接 的主机或设备中的MAC表项,从而把用户流量引到新的Master设备上来,整个过程对用户 完全透明。
5.原Master设备故障恢复时 ,若该设备为IP地址拥有者(则其优先级为255) , 将直接切换至 Master状态。若该设备优先级小于255 ,将首先切换至Backup状态，且其优先级恢复为 故障前配置的优先级。
6. Backup设备的优先级高于Master设备时，
由Backup设备的工作方式(抢占方式和非抢占方式)决定是否重新选举Master。
配置：
R1配置:
<Huawei>sys
Enter system view, return user view with Ctrl+Z.
[Huawei]un in en
Info: Information center is disabled.
[Huawei]us
[Huawei]user-in
[Huawei]user-interface con
[Huawei]user-interface console 0
[Huawei-ui-console0]i
[Huawei-ui-console0]idle-timeout 0 0
[Huawei-ui-console0]q
[Huawei]sys R1
[R1]int g0/0/0
[R1-GigabitEthernet0/0/0]ip add 13.0.0.2 24
[R1-GigabitEthernet0/0/0]un shu
Info: Interface GigabitEthernet0/0/0 is not shutdown.
[R1-GigabitEthernet0/0/0]int g0/0/1
[R1-GigabitEthernet0/0/1]ip add 23.0.0.2 24
[R1-GigabitEthernet0/0/1]un shu
Info: Interface GigabitEthernet0/0/1 is not shutdown.
[R1-GigabitEthernet0/0/1]q
[R1]int l
[R1]int LoopBack 1
[R1-LoopBack1]ip add 30.0.0.1 24
[R1-LoopBack1]q
[R1]dis ip br
^
Error: Unrecognized command found at '^' position.
[R1]dis ip int b
[R1]dis ip int brief
*down: administratively down
^down: standby
(l): loopback
(s): spoofing
The number of interface that is UP in Physical is 4
The number of interface that is DOWN in Physical is 1
The number of interface that is UP in Protocol is 4
The number of interface that is DOWN in Protocol is 1
Interface IP Address/Mask Physical Protocol
GigabitEthernet0/0/0 13.0.0.2/24 up up
GigabitEthernet0/0/1 23.0.0.2/24 up up
GigabitEthernet0/0/2 unassigned down down
LoopBack1 30.0.0.1/24 up up(s)
NULL0 unassigned up up(s)
[R1]q
<R1>sa
The current configuration will be written to the device.
Are you sure to continue? (y/n)[n]:y
It will take several minutes to save configuration file, please wait.......
Configuration file had been saved successfully
Note: The configuration file will take effect after being activated
<R1>
SW1配置：
<Huawei>sys
Enter system view, return user view with Ctrl+Z.
[Huawei]un in en
Info: Information center is disabled.
[Huawei]us
[Huawei]user-in
[Huawei]user-interface con
[Huawei]user-interface console 0
[Huawei-ui-console0]i
[Huawei-ui-console0]idle-timeout 0 0
[Huawei-ui-console0]q
[Huawei]sys SW1
[SW1]v b 10 20
Info: This operation may take a few seconds. Please wait for a moment...done.
[SW1]int e0/0/1
[SW1-Ethernet0/0/1]p l a
[SW1-Ethernet0/0/1]p d v 10
[SW1-Ethernet0/0/1]un shu
Info: Interface Ethernet0/0/1 is not shutdown.
[SW1-Ethernet0/0/1]int e0/0/2
[SW1-Ethernet0/0/2]p l a
[SW1-Ethernet0/0/2]p d v 20
[SW1-Ethernet0/0/2]un shu
Info: Interface Ethernet0/0/2 is not shutdown.
[SW1-Ethernet0/0/2]int e0/0/3
[SW1-Ethernet0/0/3]p l t
[SW1-Ethernet0/0/3]p t a v a
[SW1-Ethernet0/0/3]
[SW1-Ethernet0/0/3]int e0/0/4
[SW1-Ethernet0/0/4]p l t
[SW1-Ethernet0/0/4]p t a v a
[SW1-Ethernet0/0/4]un shu
Info: Interface Ethernet0/0/4 is not shutdown.
[SW1-Ethernet0/0/4]int e0/0/3
[SW1-Ethernet0/0/3]un shu
Info: Interface Ethernet0/0/3 is not shutdown.
[SW1-Ethernet0/0/3]q
[SW1]q
<SW1>sa
The current configuration will be written to the device.
Are you sure to continue?[Y/N]y
Info: Please input the file name ( *.cfg, *.zip ) [vrpcfg.zip]:
Now saving the current configuration to the slot 0.
Save the configuration successfully.
<SW1>
SW2配置：
<Huawei>sys
Enter system view, return user view with Ctrl+Z.
[Huawei]un in en
Info: Information center is disabled.
[Huawei]us
[Huawei]user-in
[Huawei]user-interface con
[Huawei]user-interface console 0
[Huawei-ui-console0]i
[Huawei-ui-console0]idle-timeout 0 0
[Huawei-ui-console0]q
[Huawei]sys SW2
[SW2]v b 10 20 100
Info: This operation may take a few seconds. Please wait for a moment...done.
[SW2]int g0/0/1
[SW2-GigabitEthernet0/0/1]p l t
[SW2-GigabitEthernet0/0/1]p t a v a
[SW2-GigabitEthernet0/0/1]un shu
Info: Interface GigabitEthernet0/0/1 is not shutdown.
[SW2-GigabitEthernet0/0/1]dis th
#
interface GigabitEthernet0/0/1
port link-type trunk
port trunk allow-pass vlan 2 to 4094
#
return
[SW2-GigabitEthernet0/0/1]int g0/0/2
[SW2-GigabitEthernet0/0/2]p l a
[SW2-GigabitEthernet0/0/2]p d v 100
[SW2-GigabitEthernet0/0/2]un shu
Info: Interface GigabitEthernet0/0/2 is not shutdown.
[SW2-GigabitEthernet0/0/2]dis th
#
interface GigabitEthernet0/0/2
port link-type access
port default vlan 100
#
return
[SW2-GigabitEthernet0/0/2]q
[SW2]int v
[SW2]int Vlanif 10
[SW2-Vlanif10]ip add 192.168.10.100 24
[SW2-Vlanif10]un shu
Info: Interface Vlanif10 is not shutdown.
[SW2-Vlanif10]int Vlanif 20
[SW2-Vlanif20]ip add 192.168.20.100 24
[SW2-Vlanif20]un shu
Info: Interface Vlanif20 is not shutdown.
[SW2-Vlanif20]int v
[SW2-Vlanif20]int vl
[SW2-Vlanif20]int vl
[SW2-Vlanif20]int vlanif 100
[SW2-Vlanif100]ip add 13.0.0.1 24
[SW2-Vlanif100]un shu
Info: Interface Vlanif100 is not shutdown.
[SW2-Vlanif100]q
[SW2]int v
[SW2]int Vlanif 10
[SW2-Vlanif10]vrr
[SW2-Vlanif10]vrrp v
[SW2-Vlanif10]vrrp vrid 10 vi
[SW2-Vlanif10]vrrp vrid 10 virtual-ip 192.168.10.1
[SW2-Vlanif10]vrr
[SW2-Vlanif10]vrrp v
[SW2-Vlanif10]vrrp vrid 10
[SW2-Vlanif10]vrrp vrid 10 p
[SW2-Vlanif10]vrrp vrid 10 pri
[SW2-Vlanif10]vrrp vrid 10 priority 120
[SW2-Vlanif10]vrrp
[SW2-Vlanif10]vrrp v
[SW2-Vlanif10]vrrp vrid 10 pr
[SW2-Vlanif10]vrrp vrid 10 pree
[SW2-Vlanif10]vrrp vrid 10 preempt-mode ti
[SW2-Vlanif10]vrrp vrid 10 preempt-mode timer de
[SW2-Vlanif10]vrrp vrid 10 preempt-mode timer delay 3
[SW2-Vlanif10]vr
[SW2-Vlanif10]vrrpv
[SW2-Vlanif10]vrrp v
[SW2-Vlanif10]vrrp vrid 10 t
[SW2-Vlanif10]vrrp vrid 10 tr
[SW2-Vlanif10]vrrp vrid 10 track int
[SW2-Vlanif10]vrrp vrid 10 track interface g0/0/2 re
[SW2-Vlanif10]vrrp vrid 10 track interface g0/0/2 reduced 30
[SW2-Vlanif10]q
[SW2]int vl
[SW2]int Vlanif 20
[SW2-Vlanif20]vrr
[SW2-Vlanif20]vrrp v
[SW2-Vlanif20]vrrp vrid 20 vi
[SW2-Vlanif20]vrrp vrid 20 virtual-ip 192.168.20.1
[SW2-Vlanif20]q
[SW2]q
<SW2>sa
The current configuration will be written to the device.
Are you sure to continue?[Y/N]y
Info: Please input the file name ( *.cfg, *.zip ) [vrpcfg.zip]:
Now saving the current configuration to the slot 0.
Save the configuration successfully.
<SW2>
SW3配置：
<Huawei>sys
Enter system view, return user view with Ctrl+Z.
[Huawei]un in en
Info: Information center is disabled.
[Huawei]us
[Huawei]user-in
[Huawei]user-interface con
[Huawei]user-interface console 0
[Huawei-ui-console0]i
[Huawei-ui-console0]idle-timeout 0 0
[Huawei-ui-console0]q
[Huawei]sys SW3
[SW3]int g0/0/1
[SW3-GigabitEthernet0/0/1]q
[SW3]v b 10 20 100
Info: This operation may take a few seconds. Please wait for a moment...done.
[SW3]int g0/0/1
[SW3-GigabitEthernet0/0/1]p l a
[SW3-GigabitEthernet0/0/1]p t a v a
^
Error:Ambiguous command found at '^' position.
[SW3-GigabitEthernet0/0/1]p l t
[SW3-GigabitEthernet0/0/1]p t a v a
[SW3-GigabitEthernet0/0/1]int g0/0/2
[SW3-GigabitEthernet0/0/2]p l a
[SW3-GigabitEthernet0/0/2]p d v 100
[SW3-GigabitEthernet0/0/2]un shu
Info: Interface GigabitEthernet0/0/2 is not shutdown.
[SW3-GigabitEthernet0/0/2]q
[SW3]int v
[SW3]int Vlanif 10
[SW3-Vlanif10]ip add 192.168.10.200 24
[SW3-Vlanif10]un shu
Info: Interface Vlanif10 is not shutdown.
[SW3-Vlanif10]int Vlanif 20
[SW3-Vlanif20]ip add 192.168.20.200 24
[SW3-Vlanif20]un shu
Info: Interface Vlanif20 is not shutdown.
[SW3-Vlanif20]int vlan
[SW3-Vlanif20]int vlanif 100
[SW3-Vlanif100]ip add 23.0.0.1 24
[SW3-Vlanif100]un shu
Info: Interface Vlanif100 is not shutdown.
[SW3-Vlanif100]di in br
PHY: Physical
*down: administratively down
(l): loopback
(s): spoofing
(b): BFD down
(e): ETHOAM down
(dl): DLDP down
(d): Dampening Suppressed
InUti/OutUti: input utility/output utility
Interface PHY Protocol InUti OutUti inErrors outErrors
GigabitEthernet0/0/1 up up 0% 0% 0 0
GigabitEthernet0/0/2 up up 0% 0% 0 0
GigabitEthernet0/0/3 down down 0% 0% 0 0
GigabitEthernet0/0/4 down down 0% 0% 0 0
GigabitEthernet0/0/5 down down 0% 0% 0 0
GigabitEthernet0/0/6 down down 0% 0% 0 0
GigabitEthernet0/0/7 down down 0% 0% 0 0
GigabitEthernet0/0/8 down down 0% 0% 0 0
GigabitEthernet0/0/9 down down 0% 0% 0 0
GigabitEthernet0/0/10 down down 0% 0% 0 0
GigabitEthernet0/0/11 down down 0% 0% 0 0
GigabitEthernet0/0/12 down down 0% 0% 0 0
GigabitEthernet0/0/13 down down 0% 0% 0 0
GigabitEthernet0/0/14 down down 0% 0% 0 0
GigabitEthernet0/0/15 down down 0% 0% 0 0
GigabitEthernet0/0/16 down down 0% 0% 0 0
GigabitEthernet0/0/17 down down 0% 0% 0 0
GigabitEthernet0/0/18 down down 0% 0% 0 0
GigabitEthernet0/0/19 down down 0% 0% 0 0
GigabitEthernet0/0/20 down down 0% 0% 0 0
GigabitEthernet0/0/21 down down 0% 0% 0 0
GigabitEthernet0/0/22 down down 0% 0% 0 0
GigabitEthernet0/0/23 down down 0% 0% 0 0
GigabitEthernet0/0/24 down down 0% 0% 0 0
MEth0/0/1 down down 0% 0% 0 0
NULL0 up up(s) 0% 0% 0 0
Vlanif1 up down -- -- 0 0
Vlanif10 up up -- -- 0 0
Vlanif20 up up -- -- 0 0
Vlanif100 up up -- -- 0 0
[SW3-Vlanif100]q
[SW3]int v
[SW3]int Vlanif 10
[SW3-Vlanif10]vrr
[SW3-Vlanif10]vrrp v
[SW3-Vlanif10]vrrp vrid 10 v
[SW3-Vlanif10]vrrp vrid 10 virtual-ip 192.168.10.1
[SW3-Vlanif10]vr
[SW3-Vlanif10]vrrp v
[SW3-Vlanif10]vrrp vrid 10 p
[SW3-Vlanif10]vrrp vrid 10 pri
[SW3-Vlanif10]vrrp vrid 10 priority 115
[SW3-Vlanif10]q
[SW3]in
[SW3]int
[SW3]int vl
[SW3]int Vlanif 20
[SW3-Vlanif20]vrr
[SW3-Vlanif20]vrrp v
[SW3-Vlanif20]vrrp vrid 20 v
[SW3-Vlanif20]vrrp vrid 20 virtual-ip 192.168.20.1
[SW3-Vlanif20]v
[SW3-Vlanif20]vrrp v
[SW3-Vlanif20]vrrp vrid 20 pri
[SW3-Vlanif20]vrrp vrid 20 priority 120
[SW3-Vlanif20]v
[SW3-Vlanif20]vrrp v
[SW3-Vlanif20]vrrp vrid 20 tr
[SW3-Vlanif20]vrrp vrid 20 track in
[SW3-Vlanif20]vrrp vrid 20 track interface g0/0/2 re
[SW3-Vlanif20]vrrp vrid 20 track interface g0/0/2 reduced 30
[SW3-Vlanif20]q
[SW3]dis vr
[SW3]dis vrrp
Vlanif10 | Virtual Router 10
State : Backup
Virtual IP : 192.168.10.1
Master IP : 192.168.10.100
PriorityRun : 115
PriorityConfig : 115
MasterPriority : 120
Preempt : YES Delay Time : 0 s
TimerRun : 1 s
TimerConfig : 1 s
Auth type : NONE
Virtual MAC : 0000-5e00-010a
Check TTL : YES
Config type : normal-vrrp
Create time : 2021-10-19 15:32:11 UTC-08:00
Last change time : 2021-10-19 15:32:11 UTC-08:00
Vlanif20 | Virtual Router 20
State : Master
Virtual IP : 192.168.20.1
Master IP : 192.168.20.200
PriorityRun : 120
PriorityConfig : 120
MasterPriority : 120
Preempt : YES Delay Time : 0 s
TimerRun : 1 s
TimerConfig : 1 s
Auth type : NONE
Virtual MAC : 0000-5e00-0114
Check TTL : YES
Config type : normal-vrrp
Track IF : GigabitEthernet0/0/2 Priority reduced : 30
IF state : UP
Create time : 2021-10-19 15:32:51 UTC-08:00
Last change time : 2021-10-19 15:33:03 UTC-08:00
[SW3]q
<SW3>sa
The current configuration will be written to the device.
Are you sure to continue?[Y/N]y
Info: Please input the file name ( *.cfg, *.zip ) [vrpcfg.zip]:
Now saving the current configuration to the slot 0.
Save the configuration successfully.
<SW3>
------以上就vrrp与简单配置，谢谢！
