3750交换机（EMI）简明配置维护手册目录说明 (2)产品特性 (2)配置端口 (3)配置一组端口 (3)配置二层端口 (5)配置端口速率及双工模式 (5)端口描述 (6)配置三层口 (7)监控及维护端口 (9)监控端口和控制器的状态 (9)刷新、重置端口及计数器 (11)关闭和打开端口 (12)配置VLAN (13)理解VLAN (13)可支持的VLAN (14)配置正常范围的VLAN (14)生成、修改以太网VLAN (14)删除VLAN (16)将端口分配给一个VLAN (17)配置VLAN Trunks (18)使用STP实现负载均衡 (21)说明本手册只包括日常使用的有关命令及特性，其它未涉及的命令及特性请参考英文的详细配置手册。

产品特性3750EMI是支持二层、三层功能（EMI）的交换机支持VLAN•到1005 个VLAN•支持VLAN ID从1到4094（IEEE 802.1Q 标准）•支持ISL及IEEE 802.1Q封装安全•支持IOS标准的密码保护•静态MAC地址映射•标准及扩展的访问列表支持，对于路由端口支持入出双向的访问列表，对于二层端口支持入的访问列表•支持基于VLAN的访问列表3层支持（需要多层交换的IOS）•HSRP•IP路由协议o RIP versions 1 and 2o OSPFo IGRP及EIGRPo BGP Version 4监视•交换机LED指示端口状态•SPAN及远端SPAN (RSPAN) 可以监视任何端口或VLAN的流量•内置支持四组的RMON监控功能（历史、统计、告警及事件）•Syslog功能其它功能：支持以下的GBIC模块:•1000BASE-T GBIC: 铜线最长100 m•1000BASE-SX GBIC: 光纤最长1804 feet (550 m)•1000BASE-LX/LH GBIC: 光纤最长32,808 feet (6 miles or 10 km)•1000BASE-ZX GBIC: 光纤最长328,084 feet (62 miles or 100 km) 配置端口配置一组端口当使用interface range命令时有如下的规则:•有效的组范围:o vlan从1 到4094o fastethernet槽位/{first port} - {last port}, 槽位为0o gigabitethernet槽位/{first port} - {last port},槽位为0o port-channel port-channel-number - port-channel-number, port-channel号从1到64•端口号之间需要加入空格，如：interface range fastethernet 0/1 – 5是有效的，而interface range fastethernet 0/1-5是无效的.•interface range命令只能配置已经存在的interface vlan•所有在同一组的端口必须是相同类别的。

见以下例子:Switch# configure terminalSwitch(config)# interface range fastethernet0/1 - 5Switch(config-if-range)# no shutdownSwitch(config-if-range)#*Oct 6 08:24:35: %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state to up*Oct 6 08:24:35: %LINK-3-UPDOWN: Interface FastEthernet0/2, changed state to up*Oct 6 08:24:35: %LINK-3-UPDOWN: Interface FastEthernet0/3, changed state to up*Oct 6 08:24:35: %LINK-3-UPDOWN: Interface FastEthernet0/4, changed state to up*Oct 6 08:24:35: %LINK-3-UPDOWN: Interface FastEthernet0/5, changed state to up*Oct 6 08:24:36: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/05, changed state to up*Oct 6 08:24:36: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/3, changedstate to up*Oct 6 08:24:36: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/4, changedstate to up以下的例子显示使用句号来配置不同类型端口的组:Switch# configure terminalSwitch(config)# interface range fastethernet0/1 - 3, gigabitethernet0/1 - 2Switch(config-if-range)# no shutdownSwitch(config-if-range)#*Oct 6 08:29:28: %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state to up*Oct 6 08:29:28: %LINK-3-UPDOWN: Interface FastEthernet0/2, changed state to up*Oct 6 08:29:28: %LINK-3-UPDOWN: Interface FastEthernet0/3, changed state to up*Oct 6 08:29:28: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to up *Oct 6 08:29:28: %LINK-3-UPDOWN: Interface GigabitEthernet0/2, changed state to up *Oct 6 08:29:29: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/ 1, changed state to up*Oct 6 08:29:29: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/ 2, changed state to up*Oct 6 08:29:29: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/ 3, changed state to up配置二层端口3750的所有端口缺省的端口都是二层口，如果此端口已经配置成三层端口的话，则需要用switchport来使其成为二层端口。

配置端口速率及双工模式可以配置快速以太口的速率为10/100Mbps及千兆以太口的速率为10/100/1000-Mbps; 但对于GBIC端口则不能配置速率及双工模式，有时可以配置nonegotiate,当需要联接不支持自适应的其它千兆端口时Switch# configure terminalSwitch(config)# interface fastethernet0/3 Switch(config-if)# speed 10Switch(config-if)# duplex half端口描述descriptionorshow running-configStep 6 copy running-config startup-config保存Use the no description interface configuration command to delete the description.This example shows how to add a description on Fast Ethernet interface 0/4 and to verify the description:Switch# config terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)# interface fastethernet0/4Switch(config-if)# description Connects to MarketingSwitch(config-if)# endSwitch# show interfaces fastethernet0/4 descriptionInterface Status Protocol DescriptionFa0/4 up down Connects to Marketing配置三层口Catalyst 3750支持三种类型的三层端口:•SVIs: 即interface vlanNote当生成一个interface Vlan时，只有当把某一物理端口分配给它时才能被激活•三层以太网通道口（EtherChannel）•.路由口：路由口是指某一物理端口在端口配置状态下用no switchport命令生成的端口所有的三层都需要IP地址以实现路由交换配置步骤如下：配置举例如下：Switch# configure terminalEnter configuration commands, one per line. End with CNTL/Z. Switch(config)# interface gigabitethernet0/2Switch(config-if)# no switchportSwitch(config-if)# ip address 192.20.135.21 255.255.255.0Switch(config-if)# no shutdownSwitch(config-if)# endshow ip interface命令:Switch# show ip interface gigabitethernet0/2GigabitEthernet0/2 is up, line protocol is upInternet address is 192.20.135.21/24Broadcast address is 255.255.255.255Address determined by setup commandMTU is 1500 bytesHelper address is not setDirected broadcast forwarding is disabled<output truncated>监控及维护端口监控端口和控制器的状态主要命令见下表：举例如下:Switch# show interfaces statusPort Name Status Vlan Duplex Speed TypeGi0/1 connected routed a-full a-100 10/100/1000Base TXGi0/2 wce server 20.20.2 disabled routed auto auto 10/100/1000Base TX Gi0/3 ip wccp web-cache notconnect routed auto auto 10/100/1000Base TX Gi0/4 notconnect routed auto auto 10/100/1000Base TX Gi0/5 notconnect routed auto auto 10/100/1000Base TX Gi0/6 disabled routed auto auto 10/100/1000Base TX Gi0/7 disabled routed auto auto 10/100/1000Base TX Gi0/8 disabled routed auto 100 10/100/1000Base TX Gi0/9 notconnect routed auto auto 10/100/1000Base TX Gi0/10 notconnect routed auto auto 10/100/1000Base TX Gi0/11 disabled routed auto auto unknownGi0/12 notconnect routed auto auto unknownSwitch# show interfaces fastethernet 0/1 switchportName: Fa0/1Switchport: EnabledAdministrative Mode: static accessOperational Mode: downAdministrative Trunking Encapsulation: dot1q Negotiation of Trunking: OffAccess Mode VLAN: 1 (default)Trunking Native Mode VLAN: 1 (default)Trunking VLANs Enabled: ALLPruning VLANs Enabled: 2-1001Protected: falseUnknown unicast blocked: disabledUnknown multicast blocked: disabledVoice VLAN: dot1p (Inactive)Appliance trust: 5Switch# show running-config interface fastethernet0/2 Building configuration...Current configuration : 131 bytes!interface FastEthernet0/2switchport mode accessswitchport protectedno ip addressmls qos cos 7mls qos cos overrideend刷新、重置端口及计数器clear line [number | console 0 | vty number] 重置异步串口的硬件逻辑Note clear counters 命令只清除用show interface所显示的计数，不影响用snmp得到的计数举例如下：Switch# clear counters fastethernet0/5Clear "show interface" counters on this interface [confirm] ySwitch#*Sep 30 08:42:55: %CLEAR-5-COUNTERS: Clear counter on interface FastEthernet0/5by vty1 (171.69.115.10)可使用clear interface或clear line命令来清除或重置某一端口或串口，在大部分情况下并不需要这样做:Switch# clear interface fastethernet0/5关闭和打开端口命令目的Step 1 configure terminal进入配置状态Step 2 interface {vlan vlan-id} | {{fastethernet | gigabitethernet} interface-id} | {port-channelport-channel-number} 选择要关闭的端口Step 3 shutdown关闭Step 4 end退出Step 5 show running-config验证使用no shutdown命令重新打开端口.举例如下:Switch# configure terminalSwitch(config)# interface fastethernet0/5Switch(config-if)# shutdownSwitch(config-if)#*Sep 30 08:33:47: %LINK-5-CHANGED: Interface FastEthernet0/5, changed state to a administratively downSwitch# configure terminalSwitch(config)# interface fastethernet0/5Switch(config-if)# no shutdownSwitch(config-if)#*Sep 30 08:36:00: %LINK-3-UPDOWN: Interface FastEthernet0/5, changed state to up 配置VLAN理解VLAN一个VLAN就是一个交换网，其逻辑上按功能、项目、应用来分而不必考虑用户的物理位置。