下一代互聯(lián)網(wǎng)（IPv6）搭建與運維（初級 ） 課件任務12 配置生成樹

單元1配置交換機任務12配置生成樹任務情景祥云公司由于交換機數(shù)量的增加和連接的復雜性，交換機之間具有冗余鏈路本來是一件很好的事情，但是它有可能引起的問題比它能夠解決的問題還要多。如果準備兩條以上的路，就必然形成一個環(huán)路，交換機并不知道如何處理環(huán)路，只有周而復始地轉發(fā)幀，形成一個“死環(huán)路”，這個死環(huán)路會造成整個網(wǎng)絡處于阻塞狀態(tài)，導致網(wǎng)絡癱瘓。采用生成樹協(xié)議可以避免環(huán)路。任務拓撲，如圖1-12-1所示。拓撲說明：交換機2臺、PC機2臺、Console線1根、網(wǎng)線6根圖

1-12-1網(wǎng)絡拓撲

任務情景

任務需求1.按照拓撲圖連接網(wǎng)絡。2.交換機端口規(guī)劃見表1-12-1。

表1-12-1交換機端口規(guī)劃SW-1SW-2SW-1SW-2PC1SW-1PC2SW-1PC3SW-2PC4SW-2如果多實例生成樹成功，則通過Showspanning-treemst觀察到不同實例中trunk鏈路的阻塞狀況，實現(xiàn)VLAN100只通過23口，VLAN200只通過24口，用多實例生成樹完成數(shù)據(jù)流量的負載均衡。了解生成樹的作用及應用配置生成樹學習目標任務分析默認下交換機所有端口屬于VLAN1，并分別在兩臺交換機連接PC1和PC2作為測試，當沒有在交換機上啟用生成樹協(xié)議時，用兩條網(wǎng)絡連接兩臺交換機將導致形成廣播風暴，不一會兒，交換機出現(xiàn)死機狀態(tài)，PC1和PC2不能正常通信，因此必須在兩臺交換機啟用生成樹協(xié)議來阻止因交換機物理環(huán)路死機的現(xiàn)象。預備知識生成樹協(xié)議（英語：SpanningTreeProtocol，STP），是一種工作在OSI網(wǎng)絡模型中的第二層(數(shù)據(jù)鏈路層)的通信協(xié)議，基本應用是防止交換機冗余鏈路產(chǎn)生的環(huán)路.用于確保以太網(wǎng)中無環(huán)路的邏輯拓撲結構.從而避免了廣播風暴,大量占用交換機的資源。多生成樹協(xié)議MSTP（MultipleSpanningTreeProtocol）是IEEE802.1s中定義的生成樹協(xié)議，通過生成多個生成樹，來解決以太網(wǎng)環(huán)路問題。在以太網(wǎng)中部署MSTP協(xié)議后可實現(xiàn)如下功能：形成多棵無環(huán)路的樹，解決廣播風暴并實現(xiàn)冗余備份；多棵生成樹在VLAN間實現(xiàn)負載均衡，不同VLAN的流量按照不同的路徑轉發(fā)。任務實施第1步：正確連接網(wǎng)線，恢復出廠設置之后，配置交換機的VLAN信息，配置端口到vlan的映射關系。SW-1：SW-1#configSW-1(Config)#vlan10SW-1(Config-VLAN10)#switchportinterfaceethernet1/0/1-10SettheportEthernet1/0/1accessvlan10successfullySettheportEthernet1/0/2accessvlan10successfullySettheportEthernet1/0/3accessvlan10successfullySettheportEthernet1/0/4accessvlan10successfullySettheportEthernet1/0/5accessvlan10successfullySettheportEthernet1/0/6accessvlan10successfullySettheportEthernet1/0/7accessvlan10successfullySettheportEthernet1/0/8accessvlan10successfullySettheportEthernet1/0/9accessvlan10successfullySettheportEthernet1/0/10accessvlan10successfully任務實施SW-1(Config-VLAN10)#exitSW-1(Config)#vlan20SW-1(Config-VLAN20)#switchportinterfaceethernet1/0/11-20SettheportEthernet1/0/11accessvlan20successfullySettheportEthernet1/0/12accessvlan20successfullySettheportEthernet1/0/13accessvlan20successfullySettheportEthernet1/0/14accessvlan20successfullySettheportEthernet1/0/15accessvlan20successfullySettheportEthernet1/0/16accessvlan20successfullySettheportEthernet1/0/17accessvlan20successfullySettheportEthernet1/0/18accessvlan20successfullySettheportEthernet1/0/19accessvlan20successfullySettheportEthernet1/0/20accessvlan20successfullySW-1(Config-VLAN20)#exitSW-1(Config)#interfaceethernet1/0/23-24SW-1(Config-If-Port-Range)#switchportmodetrunkSettheportEthernet1/0/23modeTRUNKsuccessfullySettheportEthernet1/0/24modeTRUNKsuccessfullySW-1(Config-If-Port-Range)#exitSW-1(Config)#任務實施SW-2：SW-2#configSW-2(Config)#vlan10SW-2(Config-VLAN10)#switchportinterfaceethernet1/0/1-10SettheportEthernet1/0/1accessvlan10successfullySettheportEthernet1/0/2accessvlan10successfullySettheportEthernet1/0/3accessvlan10successfullySettheportEthernet1/0/4accessvlan10successfullySettheportEthernet1/0/5accessvlan10successfullySettheportEthernet1/0/6accessvlan10successfullySettheportEthernet1/0/7accessvlan10successfullySettheportEthernet1/0/8accessvlan10successfullySettheportEthernet1/0/9accessvlan10successfullySettheportEthernet1/0/10accessvlan10successfullySW-2(Config-VLAN10)#exit任務實施SW-2(Config)#vlan20SW-2(Config-VLAN20)#switchportinterfaceethernet1/0/11-20SettheportEthernet1/0/11accessvlan20successfullySettheportEthernet1/0/12accessvlan20successfullySettheportEthernet1/0/13accessvlan20successfullySettheportEthernet1/0/14accessvlan20successfullySettheportEthernet1/0/15accessvlan20successfullySettheportEthernet1/0/16accessvlan20successfullySettheportEthernet1/0/17accessvlan20successfullySettheportEthernet1/0/18accessvlan20successfullySettheportEthernet1/0/19accessvlan20successfullySettheportEthernet1/0/20accessvlan20successfullySW-2(Config-VLAN20)#exitSW-2(Config)#interfaceethernet1/0/23-24SW-2(Config-If-Port-Range)#switchportmodetrunkSettheportEthernet1/0/23modeTRUNKsuccessfullySettheportEthernet1/0/24modeTRUNKsuccessfullySW-2(Config-If-Port-Range)#exitSW-2(Config)#任務實施第2步：配置多實例生成樹，在SW-1、SW-2上分別將

vlan10映射到實例1上；將vlan20映射到實例2上SW-1：SW-1(Config)#spanning-treemstconfigurationSW-1(Config-Mstp-Region)#namemstpSW-1(Config-Mstp-Region)#instance1vlan10SW-1(Config-Mstp-Region)#instance2vlan20SW-1(Config-Mstp-Region)#exitSW-1(Config)#spanning-treeMSTPisstartingnow,pleasewait...........MSTPisenabledsuccessfully.

SW-2：SW-2(Config)#spanning-treemstconfigurationSW-2(Config-Mstp-Region)#namemstpSW-2(Config-Mstp-Region)#instance1vlan10SW-2(Config-Mstp-Region)#instance2vlan20SW-2(Config-Mstp-Region)#exitSW-2(Config)#spanning-treeMSTPisstartingnow,pleasewait...........MSTPisenabledsuccessfully.任務實施第3步：在根交換機中配置端口在不同實例中的優(yōu)先級，確保不同實例阻塞不同端口查找根交換機：SW-1#showspanning-tree--MSTPBridgeConfigInfo--

Standard:IEEE802.1sBridgeMAC:00:03:0f:0b:f8:12BridgeTimes:MaxAge20,HelloTime2,ForwardDelay15ForceVersion:3

###########################Instance0###########################SelfBridgeId:32768-00:03:0f:0b:f8:12RootId:thisswitchExt.RootPathCost:0RegionRootId:thisswitchInt.RootPathCost:0RootPortID:0CurrentportlistinInstance0:…………任務實施從show中可以看出，SW-1是根交換機，在根交換機上修改trunk端口在不同實例中的優(yōu)先級。SW-1(Config)#interfaceethernet1/0/23SW-1(Config-If-Ethernet1/0/23)#spanning-treemst1port-priority32SW-1(Config-If-Ethernet1/0/23)#exitSW-1(Config)#interfaceethernet1/0/24SW-1(Config-If-Ethernet1/0/24)#spanning-treemst2port-priority32SW-1(Config-If-Ethernet1/0/24)#exitSW-1(Config)#任務實施第4步：配置SW-2的loopback端口，驗證多實例生成樹，配置SW-2上各vlan所屬loopback端口，保證各vlan在線。

SW-2(Config)#interfaceethernet1/0/1SW-2(Config-If-Ethernet1/0/1)#loopbackSW-2(Config-If-Ethernet1/0/1)#exitSW-2(Config)#interfaceethernet1/0/11SW-2(Config-If-Ethernet1/0/11)#loopbackSW-2(Config-If-Ethernet1/0/11)#exit

任務實施用“showspanning-treemst”，觀察各現(xiàn)象：SW-1#showspanning-treemst###########################Instance0###########################vlansmapped:1-9;11-19;21-4094SelfBridgeId:32768.00:03:0f:0b:f8:12RootId:thisswitchRootTimes:MaxAge20,HelloTime2,ForwardDelay15,maxhops20PortNameIDExtRPCIntRPCStateRoleDsgBridgeDsgPort-----------------------------------------------------------------------Ethernet1/0/1128.00100FWDDSGN32768.00030f0bf812128.001Ethernet1/0/11128.00900FWDDSGN32768.00030f0bf812128.009Ethernet1/0/23128.02300FWDDSGN32768.00030f0bf812128.023Ethernet1/0/24128.02400FWDDSGN32768.00030f0bf812128.024###########################Instance1###########################vlansmapped:10SelfBridgeId:32768-00:03:0f:0b:f8:12RootId:thisswitchPortNameIDIntRPCStateRoleDsgBridgeDsgPort--------------------------------------------------------------Ethernet1/0/1128.0010FWDDSGN32768.00030f0bf812128.001Ethernet1/0/23032.0230FWDDSGN32768.00030f0bf812032.023Ethernet1/0/24128.0240FWDDSGN32768.00030f0bf812128.024###########################Instance2###########################vlansmapped:20SelfBridgeId:32768-00:03:0f:0b:f8:12RootId:thisswitchPortNameIDIntRPCStateRoleDsgBridgeDsgPort--------------------------------------------------------------Ethernet1/0/11128.0090FWDDSGN32768.00030f0bf812128.009Ethernet1/0/23128.0230FWDDSGN32768.00030f0bf812128.023Ethernet1/0/24032.0240FWDDSGN32768.00030f0bf812032.024任務實施SW-2(config)#shspanning-treemst###########################Instance0###########################vlansmapped:1-9;11-19;21-4094SelfBridgeId:32768.00:03:0f:0f:6e:adRootId:32768.00:03:0f:0b:f8:12RootTimes:MaxAge20,HelloTime2,ForwardDelay15,maxhops19PortNameIDExtRPCIntRPCStateRoleDsgBridgeDsgPort-----------------------------------------------------------------------Ethernet1/0/1128.0010200000FWDDSGN32768.00030f0f6ead128.001Ethernet1/0/11128.0090200000FWDDSGN32768.00030f0f6ead128.009Ethernet1/0/22128.0220200000FWDDSGN32768.00030f0f6ead128.022Ethernet1/0/23128.02300FWDROOT32768.00030f0bf812128.023Ethernet1/0/24128.02400BLKALTR32768.00030f0bf812128.024###########################Instance1###########################vlansmapped:10SelfBridgeId:32768-00:03:0f:0f:6e:adRootId:32768.00:03:0f:0b:f8:12PortNameIDIntRPCStateRoleDsgBridgeDsgPort--------------------------------------------------------------Ethernet1/0/1128.001200000FWDDSGN32768.00030f0f6ead128.001Ethernet1/0/23128.0230FWDROOT32768.00030f0bf812032.023Ethernet1/0/24128.0240BLKALTR32768.00030f0bf812128.024###########################Instance2###########################vlansmapped:20SelfBridgeId:32768-00:03:0f:0f:6e:adRootId:32768.00:03:0f:0b:f8:12PortNameIDIntRPCStateRoleDsgBridgeDsgPort------------------------------