一、实验目标
掌握交换机TagVLAN的配置；
掌握三层交换机基本配置方法；
掌握三层交换机VLAN路由的配置方法；
通过三层交换机实现VLAN间相互通信；
二、实验背景
某企业有两个主要部门，技术部和销售部，分处于不同的办公室，为了安全和便于管理，对两个部门的主机进行了VLAN的划分，技术部和销售部分处于不同的VLAN。现由于业务的需求，需要销售部和技术部的主机能够相互访问，获得相应的资源，两个部门的交换机通过一台三层交换机进行了连接。
三、技术原理
三层交换机具备网络层的功能，实现VLAN间相互访问的原理是：利用三层交换机的路由功能，通过识别数据包的IP地址，查找路由表进行选路转发。三层交换机利用直连路由可以实现不同VLAN之间的互相访问。三层交换机给接口配置IP地址，采用SVI(交换虚拟接口)的方式实现VLAN间互连。SVI是指为交换机中的VLAN创建虚拟接口，并且配置IP地址。
四、实验步骤
实验拓扑
1、在二层交换机上配置VLAN2、VLAN3，分别将端口2、端口3划到VLAN2、VLAN3；
2、将二层交换机与三层交换机相连的端口Fa0/1定义为Trunk(TagVLAN)模式；
Switch>en
Switch#conft
Enterconfiguration commands, one per line. End with CNTL/Z.
Switch(config)#vlan2
Switch(config-vlan)#exit
Switch(config)#vlan3
Switch(config-vlan)#exit
Switch(config)#interfacefa0/2
Switch(config-if)#switchportaccess vlan 2
Switch(config-if)#exit
Switch(config)#interfacefa0/3
Switch(config-if)#switchportaccess vlan 3
Switch(config-if)#exit
Switch(config)#interfacefa0/1
Switch(config-if)#switchportmode trunk
%LINEPROTO-5-UPDOWN:Line protocol on Interface FastEthernet0/1, changed state to down
%LINEPROTO-5-UPDOWN:Line protocol on Interface FastEthernet0/1, changed state to up
Switch(config-if)#
3、在三层交换机上配置VLAN2、VLAN3，分别将端口2、端口3划到VLAN2、VLAN3；
Switch>en
Switch#conft
Enterconfiguration commands, one per line. End with CNTL/Z.
Switch(config)#vlan2
Switch(config-vlan)#exit
Switch(config)#vlan3
Switch(config-vlan)#exit
Switch(config)#interfacefa0/2
Switch(config-if)#switchportaccess vlan 2
Switch(config-if)#exit
Switch(config)#interfacefa0/3
Switch(config-if)#switchportaccess vlan 3
Switch(config-if)#exit
Switch(config)#
4、设置三层交换机VLAN间通信，创建VLAN2、VLAN3的虚拟接口，并配置虚拟接口VLAN2、VLAN3的IP地址；
Switch(config)#interfacevlan 2//创建VLAN2的虚拟接口
Switch(config-if)#
%LINK-5-CHANGED:Interface Vlan2, changed state to up
%LINEPROTO-5-UPDOWN:Line protocol on Interface Vlan2, changed state to up
Switch(config-if)#ipaddress 192.168.1.1 255.255.255.0//配置虚拟接口VLAN2的IP地址
Switch(config-if)#noshutdown //一定要打开vlan
Switch(config-if)#exit
Switch(config)#interfacevlan 3 //创建VLAN2的虚拟接口
Switch(config-if)#
%LINK-5-CHANGED:Interface Vlan3, changed state to up
%LINEPROTO-5-UPDOWN:Line protocol on Interface Vlan3, changed state to up
Switch(config-if)#ipaddress 192.168.2.1 255.255.255.0 //配置虚拟接口VLAN2的IP地址
Switch(config-if)#noshutdown
Switch(config-if)#end
Switch#
Switch(config)#interfacef0/1
Switch(config-if)#switchportmode trunk
Switch(config)#iprouting
配置计算机的IP地址
5、查看三层交换机路由表
Switch#showip route //注意一下什么时候才能看到路由表
Codes:C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D- EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1- OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1- OSPF external type 1, E2 - OSPF external type 2, E - EGP
i- IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS interarea
*- candidate default, U - per-user static route, o - ODR
P- periodic downloaded static route
Gatewayof last resort is not set
C 192.168.1.0/24 is directly connected, Vlan2
C 192.168.2.0/24 is directly connected, Vlan3
Switch#
6、将VLAN2、VLAN3下的主机默认网关分别设置为相应虚拟接口的IP地址；
五、验证
（如果不行 检查一下3560上的iprouting打开了吗？vlan和interface都up了吗？）
打开PC1Command Prompt
PacketTracer PC Command Line 1.0
PC>ipconfig
IPAddress......................: 192.168.1.2
SubnetMask.....................: 255.255.255.0
DefaultGateway.................: 192.168.1.1
PC>ping192.168.1.3
Pinging192.168.1.3 with 32 bytes of data:
Replyfrom 192.168.1.3: bytes=32 time=187ms TTL=128
Replyfrom 192.168.1.3: bytes=32 time=93ms TTL=128
Replyfrom 192.168.1.3: bytes=32 time=110ms TTL=128
Replyfrom 192.168.1.3: bytes=32 time=93ms TTL=128
Pingstatistics for 192.168.1.3:
Packets:Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximateround trip times in milli-seconds:
Minimum= 93ms, Maximum = 187ms, Average = 120ms
PC>ping192.168.2.2
Pinging192.168.2.2 with 32 bytes of data:
Requesttimed out.
Replyfrom 192.168.2.2: bytes=32 time=188ms TTL=127
Replyfrom 192.168.2.2: bytes=32 time=112ms TTL=127
Replyfrom 192.168.2.2: bytes=32 time=125ms TTL=127
Pingstatistics for 192.168.2.2:
Packets:Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximateround trip times in milli-seconds:
Minimum= 112ms, Maximum = 188ms, Average = 141ms
PC>ping192.168.2.3
Pinging192.168.2.3 with 32 bytes of data:
Requesttimed out.
Replyfrom 192.168.2.3: bytes=32 time=125ms TTL=127
Replyfrom 192.168.2.3: bytes=32 time=78ms TTL=127
Replyfrom 192.168.2.3: bytes=32 time=64ms TTL=127
Pingstatistics for 192.168.2.3:
Packets:Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximateround trip times in milli-seconds:
Minimum= 64ms, Maximum = 125ms, Average = 89ms