本文主要复述一遍实验过程：
做实验前要先看拓扑和要求
拓扑图和要求如下：
看完要求直接开始实验：
本实验PC机开启DHCP获取IP地址，故PC机不用配置IP地址：
首先，我们先从接入交换机开始配置：
SW3和SW4配置一样,举其中一个例子就OK！！！
接入层比较简单：
1、配置vlan，PC1为Vlan10，PC2为Vlan20
2、连接PC机端为access口，连接汇聚端为trunk口
3、配置MSTP
补充一点：
边缘端口：连接交换机连接下游的PC的接口
stp edged-port enable
边缘端口配置bpdu的保护
stp bpdu-protection
vlan batch 10 20 //可以通过vlan batch 10 20 直接创建多个Vlan
interface Ethernet0/0/1
port link-type access
port default vlan 10
stp edged-port enable
interface Ethernet0/0/2
port link-type access
port default vlan 20
stp edged-port enable
interface GigabitEthernet0/0/1
port link-type trunk
port trunk allow-pass vlan 10 20
interface GigabitEthernet0/0/2
port link-type trunk
port trunk allow-pass vlan 10 20
stp bpdu-protection//注意不是在接口下
开启MSTP
同时根据要求2，不同进程负载均衡
stp mode mstp
stp region-configuration
region-name NP
revision-level 1
instance 10 vlan 10
instance 20 vlan 20
active region-configuration
接下来看汇聚层：
SW1和SW2：讲一下SW1的配置，SW参考SW1
不要忘记开启DHCP：dhcp enable
汇聚层配置相比接入层多
1、创建Vlan
vlan batch 10 15 20 25
interface GigabitEthernet0/0/3
port link-type trunk
port trunk allow-pass vlan 10 20
interface GigabitEthernet0/0/4
port link-type trunk
port trunk allow-pass vlan 10 20
interface GigabitEthernet0/0/5
port link-type access
port default vlan 15
stp disable
interface Vlanif15
ip address 172.16.15.100 255.255.255.02、Eth-Trunk
interface Eth-Trunk12
port link-type trunk
port trunk allow-pass vlan 10 20
interface GigabitEthernet0/0/1
eth-trunk 12
interface GigabitEthernet0/0/2
eth-trunk 123、MSTP
stp mode mstp
stp region-configuration
region-name NP
revision-level 1
instance 10 vlan 10
instance 20 vlan 20
active region-configuration设置进程的主备根
SW1：
stp instance 10 root primary
stp instance 20 root secondary
SW2：
stp instance 20 root primary
stp instance 10 root secondary
stp instance 10 root primary
stp instance 20 root secondary4、VRRP
interface Vlanif10
ip address 172.16.10.100 255.255.255.0
vrrp vrid 10 virtual-ip 172.16.10.254
vrrp vrid 10 priority 105
vrrp vrid 10 track interface GigabitEthernet0/0/5
dhcp select relay //DHCP relay中继
dhcp relay server-ip 172.16.15.254
interface Vlanif20
ip address 172.16.20.101 255.255.255.0
vrrp vrid 20 virtual-ip 172.16.20.254
dhcp select relay //DHCP relay中继
dhcp relay server-ip 172.16.15.2545、OSPF
ospf 10 router-id 1.1.1.1
area 0.0.0.0
network 172.16.10.0 0.0.0.255
network 172.16.15.0 0.0.0.255
network 172.16.20.0 0.0.0.255配置SW5：
不要忘记开启DHCP：dhcp enable
vlan batch 15 25
interface GigabitEthernet0/0/1
port link-type access
port default vlan 15
stp disable //关闭stp
interface GigabitEthernet0/0/2
port link-type access
port default vlan 25
stp disable //关闭stp
创建一个环回口
int Loopback 0
ip address 5.5.5.5 24
interface Vlanif15
ip address 172.16.15.254 255.255.255.0
dhcp select global //开启全局地址池
interface Vlanif25
ip address 172.16.25.254 255.255.255.0
dhcp select global //开启全局地址池
配置IP地址池
ip pool 10
gateway-list 172.16.10.254
network 172.16.10.0 mask 255.255.255.0
dns-list 114.114.114.114
#
ip pool 20
gateway-list 172.16.20.254
network 172.16.20.0 mask 255.255.255.0
dns-list 114.114.114.114OSPF：
ospf 10 router-id 5.5.5.5
area 0.0.0.0
network 172.16.15.0 0.0.0.255
network 172.16.25.0 0.0.0.255
network 172.16.51.100 0.0.0.0
network 5.5.5.5 0.0.0.0 //宣告环回口配置完成！！！
测试一下获取IP地址情况！
PC1 ping PC2
测试SW5环回口地址5.5.5.5
通过Tracert追踪可以发现PC1和PC2走的路径不一样，实现负载均衡
当然通过配置VRRP，当SW1连接SW5的线断开，PC1数据将走向SW2去往SW5
此时PC1数据走的是SW2
