152 lines
4.8 KiB
Markdown
152 lines
4.8 KiB
Markdown
# 11.首跳冗余协议
|
||
|
||
一旦网络网关或关键节点出现故障，将对业务造成灾难性故障
|
||
|
||
而网关在大多数情况下只有一个，无法做到冗余，而本章节讨论的就是怎么对网络节点进行冗余。
|
||
|
||
|
||
|
||
## 1. HSRP
|
||
|
||
cisco私有的
|
||
|
||
|
||
|
||
比如内网中两个节点先比较各自的IP地址，地址大的最终胜出。
|
||
|
||
|
||
|
||
胜出的路由器可以响应虚拟IP地址的请求，而对用户而言，虚拟IP地址就是业务地址。
|
||
|
||
|
||
|
||
当负责响应这个虚拟IP地址的设备发生了故障，那么另外一台设备就会及时发现，并且抢过虚拟IP地址的响应。
|
||
|
||
|
||
|
||
R1,R2,R3是内网设备，R3模拟PC，R1和R2模拟网关
|
||
|
||
```
|
||
R1(config)#int lo0
|
||
R1(config-if)#ip add 1.1.1.1 255.255.255.0
|
||
R1(config-if)#ip ospf 1 area 0
|
||
R1(config-if)#int e0/0
|
||
R1(config-if)#ip add 192.168.14.1 255.255.255.0
|
||
R1(config-if)#no sh
|
||
R1(config-if)#ip ospf 1 area 0
|
||
R1(config-if)#int e0/1
|
||
R1(config-if)#ip add 192.168.123.251 255.255.255.0
|
||
R1(config-if)#no sh
|
||
=================================
|
||
R2(config)#int lo0
|
||
R2(config-if)#ip add 2.2.2.2 255.255.255.0
|
||
R2(config-if)#ip ospf 1 area 0
|
||
R2(config-if)#int e0/0
|
||
R2(config-if)#ip add 192.168.24.2 255.255.255.0
|
||
R2(config-if)#no sh
|
||
R2(config-if)#ip ospf 1 area 0
|
||
R2(config-if)#int e0/1
|
||
R2(config-if)#ip add 192.168.123.252 255.255.255.0
|
||
R2(config-if)#no sh
|
||
=====================================
|
||
R3(config)#int e0/0
|
||
R3(config-if)#ip add 192.168.123.3 255.255.255.0
|
||
R3(config-if)#no sh
|
||
R3(config-if)#ip route 0.0.0.0 0.0.0.0 192.168.123.254
|
||
=========================================
|
||
R4(config)#int lo0
|
||
R4(config-if)#ip add 4.4.4.4 255.255.255.0
|
||
R4(config-if)#ip ospf 1 area 0
|
||
R4(config-if)#int e0/0
|
||
R4(config-if)#ip add 192.168.14.4 255.255.255.0
|
||
R4(config-if)#no sh
|
||
R4(config-if)#ip ospf 1 area 0
|
||
R4(config-if)#int e0/1
|
||
R4(config-if)#ip add 192.168.24.4 255.255.255.0
|
||
R4(config-if)#no sh
|
||
R4(config-if)#ip ospf 1 area 0
|
||
```
|
||
|
||
配置HSRP
|
||
|
||
```
|
||
R1和R2
|
||
interface Ethernet0/1
|
||
standby 1 ip 192.168.123.254
|
||
```
|
||
|
||
查看HSRP运行状态
|
||
|
||
```
|
||
R1#sh standby
|
||
Ethernet0/1 - Group 1
|
||
State is Active
|
||
2 state changes, last state change 00:00:38
|
||
Virtual IP address is 192.168.123.254 # 虚拟IP地址
|
||
Active virtual MAC address is 0000.0c07.ac01 # 虚拟MAC地址，0000.0c07.ac<standby组号>
|
||
Local virtual MAC address is 0000.0c07.ac01 (v1 default)
|
||
Hello time 3 sec, hold time 10 sec
|
||
Next hello sent in 2.560 secs
|
||
Preemption disabled # 默认角色不会被抢占
|
||
Active router is local
|
||
Standby router is 192.168.123.252, priority 100 (expires in 10.800 sec)
|
||
Priority 100 (default 100) # 优先级大的成为active
|
||
Group name is "hsrp-Et0/1-1" (default)
|
||
R1#show standby brief
|
||
P indicates configured to preempt.
|
||
|
|
||
Interface Grp Pri P State Active Standby Virtual IP
|
||
Et0/1 1 100 Active local 192.168.123.252 192.168.123.254
|
||
```
|
||
|
||
如果优先级一样的，就比较接口IP地址，大的成为active
|
||
|
||
```
|
||
R1(config)#track 1 interface e0/0 line-protocol # 追踪e0/0链路协议状态
|
||
R1(config)#int e0/1
|
||
R1(config-if)#standby 1 preempt # 开启抢占，哪个设备优先级高，就会立即变成active
|
||
R1(config-if)#standby 1 priority 110 # 修改优先级
|
||
R1(config-if)#standby 1 track 1 decrement 20 # 如果track1变成down，那么优先级降低20
|
||
```
|
||
|
||
## 2. VRRP
|
||
|
||
和HSRP功能一样，只是计时器和名词有些变化
|
||
|
||
还是上面的拓扑
|
||
|
||
```
|
||
int e0/1
|
||
vrrp 1 ip 192.168.123.254
|
||
```
|
||
|
||
查看vrrp的运行状态
|
||
|
||
```
|
||
R1#show vrrp
|
||
Ethernet0/1 - Group 1
|
||
State is Backup
|
||
Virtual IP address is 192.168.123.254
|
||
Virtual MAC address is 0000.5e00.0101
|
||
Advertisement interval is 1.000 sec # hello间隔变为了1s
|
||
Preemption enabled # 抢占默认开启
|
||
Priority is 100
|
||
Master Router is 192.168.123.252, priority is 100
|
||
Master Advertisement interval is 1.000 sec
|
||
Master Down interval is 3.609 sec (expires in 3.016 sec) # 死亡时间变为了3s
|
||
```
|
||
|
||
```
|
||
R1(config-if)#vrrp 1 priority 110
|
||
R1(config-if)#vrrp 1 preempt
|
||
R1(config-if)#vrrp 1 track 1 decrement 20
|
||
```
|
||
|
||
## 3. GLBP
|
||
|
||
协议概述
|
||
|
||
- 使得同一时间可使用多个网关，并且自动检测活跃网关。
|
||
- 每组GLBP最多可以有4台作为ip默认网关的成员路由器，这些网关被称为AVF（active virtual forwarder）
|
||
- GLBP自动管理虚拟MAC地址的分配，决定谁来负责处理转发的工作，这些功能由AVG（active virtual gateway实现）
|
||
- 因此AVG负责分发虚拟MAC，AVF负责转发数据 |