六章交换机的基本操作课件备课讲稿.doc

六章交换机的基本操作课件备课讲稿 ?1999,Cisco Systems,Inc.6-1第六章交换机基本操作?1999,Cisco Systems,Inc.cisco. ID6-2本章目标通过本章的学习，要求掌握以下内容:?掌握2层交换(桥接)的运作?了解Catalyst1900系列交换机的出厂缺省配置?掌握Catalyst1900系列交换机的配置?利用show命令确认Catalyst1900系列交换机的配置和运作?1999,Cisco Systems,Inc.cisco. ID6-3?地址学习?帧的转发/过滤?回路防止交换机的三个功能?1999,Cisco Systems,Inc.cisco. ID6-4交换机如何学习主机的位置?最初开机时MAC地址表是空的MAC地址表0260.8c01.11110260.8c01.22220260.8c01.33330260.8c01.4444E0E1E2E3A BC D?1999,Cisco Systems,Inc.cisco. ID6-5?1999,Cisco Systems,Inc.cisco. ID6-6交换机如何学习主机的位置?主机D发送数据帧给主机C?交换机通过学习数据帧的源MAC地址，记录下主机D的MAC地址对应端口E03?该数据帧转发到除端口E3以外的其它所有端口(不清楚目标主机的单点传送用泛洪方式)0260.8c01.11110260.8c01.22220260.8c01.33330260.8c01.4444E0:0260.8c01.1111E3:0260.8c01.4444E0E1E2E3D CA BMAC地址表?1999,Cisco Systems,Inc.cisco. ID6-7交换机如何过滤帧?交换机A发送数据帧给主机C?在地址表中有目标主机，数据帧不会泛洪而直接转发发E0:0260.8c01.1111E2:0260.8c01.2222E1:0260.8c01.3333E3:0260.8c01.44440260.8c01.11110260.8c01.22220260.8c01.33330260.8c01.4444E0E1E2E3X XD CA BMAC地址表?1999,Cisco Systems,Inc.cisco. ID6-8?主机D发送广播帧或多点帧?广播帧或多点帧泛洪到除源端口外的所有端口0260.8c01.11110260.8c01.22220260.8c01.33330260.8c01.4444E0E1E2E3D CA BE0:0260.8c01.1111E2:0260.8c01.2222E1:0260.8c01.3333E3:0260.8c01.4444广播帧和多点传送帧MAC地址表?1999,Cisco Systems,Inc.cisco. ID6-9冗余网络拓扑?冗余拓扑消除了由于单点故障所引致的网络不通问题?冗余拓扑却带来了广播风暴、重复帧和MAC地址表不稳定的问题网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-10广播交换机A交换机B主机X发送一广播信息广播风暴网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-11广播广播风暴交换机A交换机B主机X发送一广播信息网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-12广播交换机不停地发出广播信息广播风暴交换机A交换机B网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-13重复帧单点帧?主机X发关一单点帧给路由器Y?路由器Y的MAC地址还没有被交换机A和B学习到交换机A交换机B网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-14单点帧?主机X发送一单点帧给路由器Y?路由器Y的MAC地址还没有被交换机A和B学习到?路由器Y会收到同一帧的两个拷贝单点帧单点帧重复帧交换机A交换机B网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-15单点帧单点帧?主机X发送一单点帧给路由器Y?路由器Y的MAC地址还没有被交换机A和B学习到?交换机A和B都学习到主机X的MAC地址对应端口0端口0端口1端口0端口1MAC地址表不稳定交换机A交换机B网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-16Unicast?主机X发送一单点帧给路由器Y?路由器Y的MAC地址还没有被交换机A和B学习到?交换机A和B都学习到主机X的MAC地址对应端口0?到路由器Y的数据帧在交换机A和B上会泛洪处理?交换机A和B都错误学习到主机X的MAC地址对应端口1MAC地址表不稳定单点帧端口0端口1端口0端口1交换机A交换机B网段1网段2服务器/主机X路由器Y?1999,Cisco Systems,Inc.cisco. ID6-17?更复杂的拓扑结构可能导致多重回路?在第2层没有能够防止这种回路的机制服务器/主机工作站回路回路回路多重回路问题广播?1999,Cisco Systems,Inc.cisco. ID6-18回路的解决办法:生成树协议Spanning-Tree Protocol将某些端口置于阻塞状态就能防止冗余结构的网络拓扑中产生回路阻塞x?1999,Cisco Systems,Inc.cisco. ID6-19?每个网络只能有一个根桥?每个非根桥只能有一个根端口?每段只能有一个指派端口x指派端口(F)根端口(F)指派端口(F)非指派端口(B)根桥非根桥SW XSW Y100baseT10baseT生成树运作?1999,Cisco Systems,Inc.cisco. ID6-20交换机Y缺省的优先级32768(8000十六进制)MAC0c0022222222交接机X缺省的优先级32768(8000十六进制)MAC0c0011111111BPDU BPDU=Bridge protocoldata unit(缺省地每2秒发送BPDU数据)根桥=有最低桥识别码的桥桥识别码=桥优先级+桥MAC地址例中，哪个交换机的桥识别码最低?Root Bridge的选择?1999,Cisco Systems,Inc.cisco. ID6-21交接机Y缺省的优先级32768MAC0c0022222222交换机X缺省的优先级32768MAC0c0011111111Root bridgex端口0端口1端口0端口1100baseT10baseT指派端口(F)根端口(F)非指派端口(B)指派端口(F)端口状态?1999,Cisco Systems,Inc.cisco. ID6-22连接速率代价(修订的IEEE规范)代价(旧IEEE规范)-10Gbps211Gbps41100Mbps191010Mbps100100路径代价?1999,Cisco Systems,Inc.cisco. ID6-23交换机Y MAC0c0022222222缺省的优先级32768交换机X MAC0c0011111111缺省的优先级32768端口0端口1端口0端口1交换机Z Mac0c0011110000缺省的优先级32768端口0请指出:?根桥?指派端口、非指派端口和根端口?各端口分别是转发还是阻塞状态?100baseT100baseT生成树?1999,Cisco Systems,Inc.cisco. ID6-24端口0100baseT100baseT指派端口(F)根端口(F)非指派端口(阻塞)指派端口(F)根端口(F)请指出:?根桥?指派端口、非指派端口和根端口?各端口分别是转发还是阻塞状态?生成树交换机Y MAC0c0022222222缺省的优先级32768交换机X MAC0c0011111111缺省的优先级32768端口0端口1端口0端口1交换机Z Mac0c0011110000缺省的优先级32768?1999,Cisco Systems,Inc.cisco. ID6-25阻阻塞侦侦听学学习转转发生成树会将每个端口的状态作以下变换:生成树端口状态?1999,Cisco Systems,Inc.cisco. ID6-26交换机Y MAC0c0022222222缺省的优先级32768交换机X MAC0c0011111111缺省的优先级32768端口0端口1端口0端口110baseT x100baseT RootBridge指派端口根端口(F)非指派端口(阻塞)指派端口生成树重新生成?1999,Cisco Systems,Inc.cisco. ID6-27交换机Y MAC0c0022222222缺省优先级32768交换机X MAC0c0011111111缺省优先级32768端口0端口1端口0端口110baseT x100baseT RootBridge指派端口根端口(F)非指派端口(阻塞)指派端口BPDU xMAXAGE x生成树重新生成?1999,Cisco Systems,Inc.cisco. ID6-28关键:收敛时间?当所有交换机和桥的端口都改变到要么是转发要么是阻塞状态时发生收敛?当网络拓扑发生改变时，交换机和桥必须重新生成生成权，否则可能损及传送中的用户数据?1999,Cisco Systems,Inc.cisco. ID6-29基于软件实现每个桥只能有一个生成树每个桥通常最多到16个端口桥桥基于硬件实现(ASIC)每个交换机可以有多个生成树有更多的端口交换机桥与交换机的比较?1999,Cisco Systems,Inc.cisco. ID6-30LAN交换机的工作方式(帧交换)直通转发?交换机检测到目标地址后即转发帧Frame?1999,Cisco Systems,Inc.cisco. ID6-31LAN交换机的工作方式(帧交换)存贮转发?完整地收到帧并检查无错后才转发直通转发?交换机检测到目标地址后即转发帧Frame Frame Frame Frame?1999,Cisco Systems,Inc.cisco. ID6-32直通转发?交换机检测到目标地址后即转发帧Frame片断转发(直通转发的修订版)Cat1900的缺省模式?交换机检测到帧的前64字节后即转发Frame存贮转发?完整地收到帧并检查无错后才转发FrameFrameFrame LAN交换机的工作方式(帧交换)?1999,Cisco Systems,Inc.cisco. ID6-33半双工(CSMA/CD)?单向数据传送?冲突可能性高?用集线器连接交换机集线器双工综述?1999,Cisco Systems,Inc.cisco. ID6-34全双工?只能用于点对点?连接到特定的端口?两端均须支持全双工?无冲突?冲突检测电路关闭双工综述半双工(CSMA/CD)?单向数据传送?冲突可能性高?用集线器连接交换机集线器?1999,Cisco Systems,Inc.cisco. ID6-35配置交换机?Catalyst1900菜单界面基于Web的管理VSM(Visual SwitchManager)IOS命令行界面?1999,Cisco Systems,Inc.cisco. ID6-36?IP地址:0.0.0.0?CDP:开启?交换模式:片断转发?100baseT端口:自动协商双工模式?10baseT端口:半双工?生成树协议:开启?控制台密码:无Catalyst1900系列的缺省配置?1999,Cisco Systems,Inc.cisco. ID6-37Cat1912Cat192410baseT端口AUI端口100baseT级连端口e0/1to e0/12e0/1to e0/24e0/25e0/25fa0/26(port A)fa0/27(port B)fa0/26(port A)fa0/27(port B)Catalyst1900系列的端口?1999,Cisco Systems,Inc.cisco. ID6-38wg_sw_d#sh runBuilding configuration.Current configuration:!interface Ether0/1!interface Ether0/2wg_sw_d#sh spanPort Ether0/1of VLAN1is ForwardingPort path cost100,Port priority128Designated roothas priority32768,address0090.8673.3340Designated bridgehas priority32768,address0090.8673.3340Designated portis Ether0/1,pathcost0Timers:message age20,forward delay15,hold1wg_sw_a#show vlan-membership PortVLAN MembershipType PortVLAN MembershipType-15Static131Static21Static141Static31Static151Static Catalyst1900系列的端口?1999,Cisco Systems,Inc.cisco. ID6-39?配置模式全局配置模式wg_sw_a#conf termwg_sw_a(config)#端口配置模式wg_sw_a(config)#interface e0/1wg_sw_a(config-if)#配置交换机?1999,Cisco Systems,Inc.cisco. ID6-40配置交换机IP地址wg_sw_a(config)#ip addressip addressmask?1999,Cisco Systems,Inc.cisco. ID6-41wg_sw_a(config)#ip address10.5.5.11255.255.255.0wg_sw_a(config)#ip addressip addressmask配置交换机IP地址?1999,Cisco Systems,Inc.cisco. ID6-42wg_sw_a(config)#ip default-gatewayip address配置交换机缺省网关?1999,Cisco Systems,Inc.cisco. ID6-43wg_sw_a(config)#ip default-gateway10.5.5.3wg_sw_a(config)#ip default-gatewayip address配置交换机缺省网关?1999,Cisco Systems,Inc.cisco. ID6-44wg_sw_a#show ipIP address:10.5.5.11Sub mask:255.255.255.0Default gateway:10.5.5.3Management VLAN:1Domain name:Name server1:0.0.0.0Name server2:0.0.0.0 server:Enabled port:80RIP:Enabled wg_sw_a#显示交换机IP地址?1999,Cisco Systems,Inc.cisco. ID6-45设置双工模式wg_sw_a(config)#interface e0/1wg_sw_a(config-if)#duplexauto|full|full-flow-control|half?1999,Cisco Systems,Inc.cisco. ID6-46wg_sw_a(config-if)#duplex halfwg_sw_a(config)#interface e0/1wg_sw_a(config-if)#duplexauto|full|full-flow-control|half设置双工模式?1999,Cisco Systems,Inc.cisco. ID6-47wg_sw_a#sh interfacesEther0/1is EnabledHardware isBuilt-in10Base-T Addressis0090.8673.3341MTU1500bytes,BW10000Kbits802.1d STPState:Forwarding ForwardTransitions:1Port monitoring:Disabled Unknownunicast flooding:Enabled Unregisteredmulticast flooding:Enabled Description:Duplex setting:Half duplexBack pressure:Disabled ReceiveStatistics TransmitStatistics-Total goodframes44841Total frames404502Total octets4944550Total octets29591574Broadcast/multicast frames31011Broadcast/multicast frames390913Broadcast/multicast octets3865029Broadcast/multicast octets28478154Good framesforwarded44832Deferrals0Frames filtered9Single collisions0Runt frames0Multiple collisions0No bufferdiscards0Excessive collisions0Queue fulldiscards0Errors:Errors:FCS errors0Late collisions0Alignment errors0Excessive deferrals0Giant frames0Jabber errors0Address violations0Other transmiterrors0显示双工信息?1999,Cisco Systems,Inc.cisco. ID6-48双工不匹配?连接的两个端口人工地设置了不同的双工参数?交换机端口为自动协商模式，连接到端口的另一端设为不自动协商的全双工模式，会导致交换机的端口置于半双工模式?1999,Cisco Systems,Inc.cisco. ID6-50管理MAC地址表wg_sw_a#show mac-address-table?1999,Cisco Systems,Inc.cisco. ID6-51wg_sw_a#sh mac-address-table Number of permanentaddresses:0Number ofrestricted staticaddresses:0Number ofdynamic addresses:6Address DestInterface TypeSource InterfaceList-00E0.1E5D.AE2F Ether0/2Dynamic All00D0.588F.B604FastEther0/26Dynamic All00E0.1E5D.AE2B FastEther0/26Dynamic All0090.273B.87A4FastEther0/26Dynamic All00D0.588F.B600FastEther0/26Dynamic All00D0.5892.38C4FastEther0/27Dynamic Allwg_sw_a#show mac-address-table管理MAC地址表?1999,Cisco Systems,Inc.cisco. ID6-52wg_sw_a(config)#mac-address-table permanentmac-address typemodule/port设置永久MAC地址?1999,Cisco Systems,Inc.cisco. ID6-53wg_sw_a(config)#wg_sw_a(config)#mac-address-table permanent2222.2222.2222ether0/3mac-address-table permanentmac-address typemodule/port设置永久MAC地址?1999,Cisco Systems,Inc.cisco. ID6-54wg_sw_a#sh mac-address-table Number of permanentaddresses:1Number ofrestricted staticaddresses:0Number ofdynamic addresses:4Address DestInterface TypeSource InterfaceList-00E0.1E5D.AE2F Ether0/2Dynamic All2222.2222.2222Ether0/3Permanent All00D0.588F.B604FastEther0/26Dynamic All00E0.1E5D.AE2BFastEther0/26Dynamic All00D0.5892.38C4FastEther0/27Dynamic Allwg_sw_a(config)#wg_sw_a(config)#mac-address-table permanent2222.2222.2222ether0/3mac-address-table permanentmac-address typemodule/port设置永久MAC地址?1999,Cisco Systems,Inc.cisco. ID6-55wg_sw_a(config)#mac-address-table restricted staticmac-address typemodule/port src-if-list设置受限的静态MAC地址?1999,Cisco Systems,Inc.cisco. ID6-56wg_sw_a(config)#mac-address-table restrictedstatic1111.1111.1111e0/4e0/1wg_sw_a(config)#mac-address-table restrictedstaticmac-address typemodule/port src-if-list设置受限的静态MAC地址?1999,Cisco Systems,Inc.cisco. ID6-57wg_sw_a#sh mac-address-table Numberof permanentaddresses:1Numberofrestrictedstaticaddresses:1Numberofdynamic addresses:4Address DestInterface TypeSource InterfaceList-1111.1111.1111Ether0/4Static Et0/100E0.1E5D.AE2F Ether0/2Dynamic All2222.2222.2222Ether0/3Permanent All00D0.588F.B604FastEther0/26Dynamic All00E0.1E5D.AE2B FastEther0/26Dynamic All00D0.5892.38C4FastEther0/27Dynamic Allwg_sw_a(config)#mac-address-table restrictedstatic1111.1111.1111e0/4e0/1wg_sw_a(config)#mac-address-table restrictedstaticmac-address typemodule/port src-if-list设置受限的静态MAC地址?1999,Cisco Systems,Inc.cisco. ID6-58配置端口安全性wg_sw_a(config-if)#?将一个端口配置为一个有安全设定的端口?定义该端口在MAC地址表中对应MAC地址的最多条数?可以定义1到132?缺省为132port securemax-mac-count count?1999,Cisco Systems,Inc.cisco. ID6-59wg_sw_a(config-if)#?将一个端口配置为一个有安全限制的端口?定义该端口在MAC地址表中对应MAC地址的最多条数?可以定义1到132?缺省为132wg_sw_a(config)#interface e0/4wg_sw_a(config-if)#port securemax-mac-count1port securemax-mac-count count配置端口安全性?1999,Cisco Systems,Inc.cisco. ID6-60配置端口安全性wg_sw_a#show mac-address-table securitywg_sw_a#show mac-address-table securityAction uponaddress violation:Suspend InterfaceAddressing SecurityAddress TableSize-Ether0/1Disabled N/A Ether0/2Disabled N/A Ether0/3Disabled N/A Ether0/4Enabled1Ether0/5Disabled N/A Ether0/6Disabled N/A Ether0/7Disabled N/A Ether0/8Disabled N/A Ether0/9Disabled N/A Ether0/10Disabled N/A Ether0/11Disabled N/A Ether0/12Disabled N/A?1999,Cisco Systems,Inc.cisco. ID6-61wg_sw_a#show mac-address-table securitywg_sw_a(config)#address-violationsuspend|disable|ignorewg_sw_a#show mac-address-table securityAction uponaddress violation:Suspend InterfaceAddressing SecurityAddress TableSize-Ether0/1Disabled N/A Ether0/2Disabled N/A Ether0/3Disabled N/A Ether0/4Enabled1Ether0/5Disabled N/A Ether0/6Disabled N/A Ether0/7Disabled N/A Ether0/8Disabled N/A Ether0/9Disabled N/A Ether0/10Disabled N/A Ether0/11Disabled N/A Ether0/12Disabled N/A配置端口安全性?1999,Cisco Systems,Inc.cisco. ID6-62wg_sw_a#show versionCisco Catalyst1900/2820Enterprise EditionSoftware VersionV8.01.01Copyright(c)Cisco Systems,Inc.1993-1998ROM:System Bootstrap,Version3.03wg_sw_d uptimeis8day(s)17hour(s)53minute(s)25second(s)cisco Catalyst1900(486sxl)processor with2048K/1024K bytesof memoryHardware boardrevision i