我備課第4天module5-2交換技術(shù)vlan

1、交換技術(shù)VLAN-TRUNK-VTPModule5-2傳統(tǒng)的網(wǎng)絡(luò)設(shè)計網(wǎng)絡(luò)范圍沒有界限廣播域范圍大大量的單播幀傳輸在網(wǎng)絡(luò)中每個角落廣播沒有界限不宜管理和維護可能的安全隱患VLAN 綜述VLAN = Broadcast Domain = Logical Network (Subnet) 分割網(wǎng)絡(luò)靈活設(shè)計安全有效VLAN的設(shè)計設(shè)計VLAN必須考慮到分級子網(wǎng)的設(shè)計 :便于管理和排錯減少錯誤信息的發(fā)送 盡量縮減路由表的大小IP地址空間的應(yīng)用指導(dǎo)方針 每個VLAN分配一個子網(wǎng).在一個共同的區(qū)域分配一個子網(wǎng).VLAN 模式VLAN Trunk（cont.）VLAN干道：對于多個VLAN交換機來說，VLAN干

2、線就是兩個交換機之間的連接，它在兩個或兩個以上的VLAN之間傳輸通信。每個交換機必須確定它所收到的幀屬于哪個VLAN。一個交換機的任何端口都必須屬于且只能屬于一個VLAN，但當端口配置成trunk干線后，該端口就失去了它自身的VLAN標識，可以為該交換機內(nèi)的所有VLAN傳輸數(shù)據(jù)。 IEEE公共幀標記協(xié)議802.1Q如果要跨越cisco交換機和其他廠商的交換機來建立多個VLAN，必須使用802.1Q協(xié)議VLAN Tag added by ing portVLAN Tag stripped by forwarding port802.1Q VLAN identifier802.1Q Frame80

3、2.1Q Trunking認識 Native VLANsConfiguring 802.1Q TrunkingConfigures the port as a VLAN trunk SwitchX(config-if)#switchport mode trunkswitchport mode access | dynamic auto | desirable | trunkSwitchX(config-if)#Configures the trunking characteristics of the portSwitchX# show interfaces fa0/11 trunkPort

4、Mode Encapsulation Status Native vlanFa0/11 desirable 802.1q trunking 1Port Vlans allowed on trunkFa0/11 1-4094Port Vlans allowed and active in management domainFa0/11 1-13SwitchX# show interfaces fa0/11 switchportName: Fa0/11Switchport: EnabledAdministrative Mode: trunkOperational Mode: downAdminis

5、trative Trunking Encapsulation: dot1qNegotiation of Trunking: OnAccess Mode VLAN: 1 (default)Trunking Native Mode VLAN: 1 (default) . . .查看 Trunk 信息SwitchX# show interfaces interface switchport | trunk 創(chuàng)建 VLAN 指導(dǎo)方針創(chuàng)建多少個VLAN取決于交換機.VLAN 1 出廠默認的 Ethernet VLAN. Cisco Discovery Protocol and VTP 公告發(fā)送信息使用

6、VLAN 1.Cisco Catalyst 交換機IP地址用作管理VLAN (VLAN 1 by default).如果使用 VTP, 必須在VTP server或VTP transparent 交換機上添加或刪除VLAN.Adding a VLANSwitchX# configure terminalSwitchX(config)# vlan 2SwitchX(config-vlan)# name switchlab99SwitchX# show vlan id 2VLAN Name Status Ports- - - -2 switchlab99 active Fa0/2, Fa0/12V

7、LAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2- - - - - - - - - - -2 enet 100002 1500 - - - - - 0 0. . .SwitchX#Verifying a VLANSwitchX# show vlan brief | id vlan-id | name vlan-name分配 交換機端口到對應(yīng) VLANSwitchX# configure terminalSwitchX(config)# interface range fastethernet 0/2 - 4S

8、witchX(config-if)# switchport access vlan 2 SwitchX# show vlanVLAN Name Status Ports- - - -1 default active Fa0/1 2 switchlab99 active Fa0/2, Fa0/3, Fa0/4switchport access vlan vlan# | dynamicSwitchX(config-if)#SwitchX# show vlan briefVLAN Name Status Ports- - - -1 default active Fa0/12 switchlab99

9、active Fa0/2, Fa0/3, Fa0/4 3 vlan3 active4 vlan4 active1002 fddi-default act/unsup1003 token-ring-default act/unsupVLAN Name Status Ports- - - -1004 fddinet-default act/unsup1005 trnet-default act/unsupSwitchX# show vlan brief查看所有VLAN 查看所有VLAN(Cont.)SwitchX# show interfaces fa0/2 switchportName: Fa0

10、/2Switchport: EnabledAdministrative Mode: dynamic autoOperational Mode: static accessAdministrative Trunking Encapsulation: dot1qOperational Trunking Encapsulation: nativeNegotiation of Trunking: OnAccess Mode VLAN: 2 (switchlab99)Trunking Native Mode VLAN: 1 (default)- output omitted -show interfaces interface switchportSwitchX(config-if)#VTP 特征不能夠創(chuàng)建，修改或刪除 VLANs 轉(zhuǎn)發(fā)VLAN通告信息同步創(chuàng)建 VLANs修改 VLANs刪除 VLANs發(fā)送