<span class="log-zd"><span class="log-close"><a title="隐藏目录"><i class="be be-cross"></i><strong>目录</strong></a></span></span>

第1章 交换基础

1.1 园区网分层结构

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  <p style="text-align: center;" align="center">
    <strong>作用</strong>
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    广域网接入
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    出口策略
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    带宽控制
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    高速转发
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    服务器接入
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    路由选择
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    流量汇聚
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    链路冗余
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    设备冗余
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    路由选择
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    用户接入
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    接入安全
  </p>
  
  <p style="text-align: justify; text-justify: inter-ideograph;">
    访问控制
  </p>
</td>

1.2 交换机的主要功能

1.3 MAC地址

1.4 交换寻址

第2章 VLAN 虚拟局域网

2.1 vlan概述

 将交换机的端口进行vlan划分(划分不同的广播域)

通过十进制数进行标识

2.2 vlan的成员模式

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  <p style="text-align: center;" align="center">
    <strong>方式</strong>
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    交换机上的端口以手动方式分配给Vlan
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    使用VMPS可以根据连接到交换机端口的设备源MAC地址,动态地将端口分配给VLAN
  </p>
</td>
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  <p style="text-align: justify; text-justify: inter-ideograph;">
    将端口配置到语音模式可以使端口支持连接到该端口的IP电话
  </p>
</td>

2.3 trunk干道

2.3.1 ISL封装协议(使用较少)

2.3.2 dot1q协议(801.1q)

数据包格式

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    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">3 bits</span>
    </p>
  </td>
  
  <td style="border-top: solid #F79646 1.0pt; border-left: none; border-bottom: solid #F79646 1.0pt; border-right: none; background: #F79646; padding: 0cm 5.4pt 0cm 5.4pt; height: 2.9pt;" valign="top">
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">1 bit</span>
    </p>
  </td>
  
  <td style="border-top: 1pt solid #f79646; border-right: 1pt solid #f79646; border-bottom: 1pt solid #f79646; border-left: none; background: #f79646; padding: 0cm 5.4pt; height: 2.9pt;" valign="top">
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">12 bits</span>
    </p>
  </td>
</tr>

<tr style="height: 22.35pt;">
  <td style="border-right: 1pt solid #fabf8f; border-bottom: 1pt solid #fabf8f; border-left: 1pt solid #fabf8f; border-top: none; background: #fde9d9; padding: 0cm 5.4pt; height: 22.35pt;" valign="top">
    <p style="text-align: center; layout-grid-mode: both; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">TPID</span>
    </p>
    
    <p style="text-align: center; layout-grid-mode: both; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt; font-family: 宋体; color: #222222;">标签协议识别符</span>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid #FABF8F 1.0pt; border-right: solid #FABF8F 1.0pt; background: #FDE9D9; padding: 0cm 5.4pt 0cm 5.4pt; height: 22.35pt;" valign="top">
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">PCP</span>
    </p>
    
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">优先权代码点</span>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid #FABF8F 1.0pt; border-right: solid #FABF8F 1.0pt; background: #FDE9D9; padding: 0cm 5.4pt 0cm 5.4pt; height: 22.35pt;" valign="top">
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">CFI</span>
    </p>
    
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">标准格式指示</span>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid #FABF8F 1.0pt; border-right: solid #FABF8F 1.0pt; background: #FDE9D9; padding: 0cm 5.4pt 0cm 5.4pt; height: 22.35pt;" valign="top">
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">VID</span>
    </p>
    
    <p style="text-align: center; margin: 12.0pt 0cm 12.0pt 0cm;" align="center">
      <span style="font-size: 11.5pt;">虚拟局域网识别符</span>
    </p>
  </td>
</tr>

2.4 VLAN的特点

2.5 cisco上vlan范围

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    <p style="margin: 0cm; margin-bottom: .0001pt; text-align: center; line-height: 13.5pt; layout-grid-mode: both;" align="center">
      <strong><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">用途</span></strong>
    </p>
  </td>
</tr>

<tr>
  <td style="border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #9bbb59; padding: 0cm 5.4pt;">
    <p style="margin: 0cm; margin-bottom: .0001pt; text-align: center; line-height: 13.5pt; layout-grid-mode: both;" align="center">
      <strong><span style="font-size: 9.0pt;"></span></strong><strong><span style="font-size: 9.0pt; font-family: 宋体; color: #984806;">、</span></strong><strong><span style="font-size: 9.0pt;">4095</span></strong>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #D6E3BC; padding: 0cm 5.4pt 0cm 5.4pt;" valign="top">
    <p style="margin: 0cm; margin-bottom: .0001pt; line-height: 13.5pt; layout-grid-mode: both;">
       <span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">保留</span>
    </p>
  </td>
</tr>

<tr>
  <td style="border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #9bbb59; padding: 0cm 5.4pt;">
    <p style="margin: 0cm; margin-bottom: .0001pt; text-align: center; line-height: 13.5pt; layout-grid-mode: both;" align="center">
      <strong><span style="font-size: 9.0pt;">1</span></strong>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #EAF1DD; padding: 0cm 5.4pt 0cm 5.4pt;" valign="top">
    <p style="margin: 0cm; margin-bottom: .0001pt; line-height: 13.5pt; layout-grid-mode: both;">
      <span style="font-size: 9.0pt;"> cisco</span><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">交换机端口默认属于</span><span style="font-size: 9.0pt;">VLAN1 </span><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">不能删除</span>
    </p>
  </td>
</tr>

<tr>
  <td style="border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #9bbb59; padding: 0cm 5.4pt;">
    <p style="margin: 0cm; margin-bottom: .0001pt; text-align: center; line-height: 13.5pt; layout-grid-mode: both;" align="center">
      <strong><span style="font-size: 9.0pt;">2-1001</span></strong>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #D6E3BC; padding: 0cm 5.4pt 0cm 5.4pt;" valign="top">
    <p style="margin: 0cm; margin-bottom: .0001pt; line-height: 13.5pt; layout-grid-mode: both;">
       <span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">用于以太网</span><span style="font-size: 9.0pt;">VLAN</span>
    </p>
  </td>
</tr>

<tr>
  <td style="border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #9bbb59; padding: 0cm 5.4pt;">
    <p style="margin: 0cm; margin-bottom: .0001pt; text-align: center; line-height: 13.5pt; layout-grid-mode: both;" align="center">
      <strong><span style="font-size: 9.0pt;">1002-1005</span></strong>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #EAF1DD; padding: 0cm 5.4pt 0cm 5.4pt;" valign="top">
    <p style="margin: 0cm; margin-bottom: .0001pt; line-height: 13.5pt; layout-grid-mode: both;">
       <span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">思科缺省用于</span><span style="font-size: 9.0pt;">FDDI</span><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">、</span><span style="font-size: 9.0pt;">Token Ring</span><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">网</span>
    </p>
  </td>
</tr>

<tr>
  <td style="border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #9bbb59; padding: 0cm 5.4pt;">
    <p style="margin: 0cm; margin-bottom: .0001pt; text-align: center; line-height: 13.5pt; layout-grid-mode: both;" align="center">
      <strong><span style="font-size: 9.0pt;">1006-4094</span></strong>
    </p>
  </td>
  
  <td style="border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #D6E3BC; padding: 0cm 5.4pt 0cm 5.4pt;" valign="top">
    <p style="margin: 0cm; margin-bottom: .0001pt; line-height: 13.5pt; layout-grid-mode: both;">
       <span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">扩展</span><span style="font-size: 9.0pt;">VLAN</span><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">,用于以太网</span><span style="font-size: 9.0pt;">VLAN</span><span style="font-size: 9.0pt; font-family: 宋体; color: #464646;">,在一些很老的平台上不支持</span>
    </p>
  </td>
</tr>

2.6 VTP (VLAN Trunking Protocol)

2.6.1 vlan使用过程

2.6.2 vtp三种模式

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    <p style="text-align: center;" align="center">
      <strong>功能</strong>
    </p>
  </td>
</tr>

<tr>
  <td style="width: 106.1pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; background: #eaf1dd; padding: 0cm 5.4pt;" width="141">
    <p style="text-align: center;" align="center">
      <strong>sever</strong>
    </p>
  </td>
  
  <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; background: #EAF1DD; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
    <p style="text-align: justify; text-justify: inter-ideograph;">
      创建VLAN、修改vlan、删除vlan
    </p>
    
    <p style="text-align: justify; text-justify: inter-ideograph;">
      发送/转发信息宣告、同步
    </p>
    
    <p style="text-align: justify; text-justify: inter-ideograph;">
      存储在NVRAM中、Catalyst交换机默认使sever模式
    </p>
  </td>
</tr>

<tr>
  <td style="width: 106.1pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; padding: 0cm 5.4pt;" width="141">
    <p style="text-align: center;" align="center">
      <strong>client</strong>
    </p>
  </td>
  
  <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
    <p style="text-align: justify; text-justify: inter-ideograph;">
      同步
    </p>
    
    <p style="text-align: justify; text-justify: inter-ideograph;">
      发送/转发信息宣告
    </p>
    
    <p style="text-align: justify; text-justify: inter-ideograph;">
      不会存储与NVRAM
    </p>
  </td>
</tr>

<tr>
  <td style="width: 106.1pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; background: #eaf1dd; padding: 0cm 5.4pt;" width="141">
    <p style="text-align: center;" align="center">
      <strong>Transparent</strong>
    </p>
  </td>
  
  <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; background: #EAF1DD; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
    <p style="text-align: justify; text-justify: inter-ideograph;">
      创建VLAN、修改vlan、删除vlan
    </p>
    
    <p style="text-align: justify; text-justify: inter-ideograph;">
      转发、信息宣告、不同步
    </p>
    
    <p style="text-align: justify; text-justify: inter-ideograph;">
      存储于NVRAM
    </p>
  </td>
</tr>

2.6.3 VTP的运作

2.6.4 VTP的修剪 Pruning

2.6.4.1 允许所有vlan通过会有什么缺点呢?

2.7 VLAN基本配置

2.7.1 创建VLAN信息

2.7.2 将端口划入特定的vlan

2.7.3 配置Trunk封装方式

2.7.4 开启端口

2.8 VTP的基本配置

2.8.1 注意:

2.9 【实验】vlan

2.9.1 拓扑图

2.9.2 交换机配置

S-vlan-1上vlan配置

S-vlan-2上VLAN配置

trunk链路配置

S-vlan-1**:**

S-vlan-1**:**

2.9.3 查看vlan信息

2.9.3.1 S-vlan-1信息

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  ---- -------------------------------- --------- -------------------------------
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  1    default                          active    Fa0/3, Fa0/4, Fa0/5, Fa0/6
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                  Fa0/7, Fa0/8, Fa0/9, Fa0/10
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                  Fa0/11, Fa0/12, Fa0/13, Fa0/14
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                  Fa0/15, Fa0/16, Fa0/17, Fa0/18
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                  Fa0/19, Fa0/20, Fa0/21, Fa0/22
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                  Fa0/23, Fa0/24, Gig0/2
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  <span style="color: #e36c0a;">10   VLAN10                           active    Fa0/1</span>
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  <span style="color: #e36c0a;">20   VLAN20                           active    Fa0/2</span>
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  1002 fddi-default                     active
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  1003 token-ring-default               active
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  1004 fddinet-default                  active
</p>

<p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
  1005 trnet-default                    active
</p></div> 

<span class="directory"></span>

<h4 id="title-1">
  <span id="2932S-vlan-2">2.9.3.2 S-vlan-2信息</span>
</h4>

<div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
    S-vlan-2#<span style="color: #e36c0a;">show vlan brief </span>
  </p>
  
  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      VLAN Name                             Status    Ports
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      ---- -------------------------------- --------- -------------------------------
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      1    default                          active    Fa0/3, Fa0/4, Fa0/5, Fa0/6
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                      Fa0/7, Fa0/8, Fa0/9, Fa0/10
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                      Fa0/11, Fa0/12, Fa0/13, Fa0/14
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                      Fa0/15, Fa0/16, Fa0/17, Fa0/18
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                      Fa0/19, Fa0/20, Fa0/21, Fa0/22
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                      Fa0/23, Fa0/24, Gig0/2
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      <span style="color: #e36c0a;">10   VLAN10                           active    Fa0/1</span>
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      <span style="color: #e36c0a;">20   VLAN20                           active    Fa0/2</span>
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      1002 fddi-default                     active
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      1003 token-ring-default               active
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      1004 fddinet-default                  active
    </p>
    
    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
      1005 trnet-default                    active
    </p></div> 
    
    <span class="directory"></span>
    
    <h4 id="title-2">
      <span id="2933trunk">2.9.3.3 查看trunk信息</span>
    </h4>
    
    <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
        S-vlan-1#show interfaces trunk
      </p>
      
      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
        Port        Mode         Encapsulation  Status        Native vlan
      </p>
      
      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
        Gig0/1      on           802.1q         trunking      1
      </p>
      
      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
          Port        Vlans allowed on trunk
        </p>
        
        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
          Gig0/1      1-1005
        </p>
        
        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
            Port        Vlans allowed and active in management domain
          </p>
          
          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
            Gig0/1      1,10,20
          </p>
          
          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
            <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
              Port        Vlans in spanning tree forwarding state and not pruned
            </p>
            
            <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
              Gig0/1      1,10,20
            </p></div> 
            
            <h2>
              <span id="210">2.10 单臂路由</span>
            </h2>
            
            <p style="margin-left: 21.0pt; text-indent: 21.0pt;">
              单臂路由(路由器上一棒)指的英文在路由器的一个接口上通过配置子接口(或“逻辑接口”,并不存在真正物理接口)的方式,实现原来相互隔离的不同VLAN(虚拟局域网)之间的互联互通。
            </p>
            
            <p style="margin-left: 42.0pt;">
              在路由器中创建子接口
            </p>
            
            <h3>
              <span id="2101">2.10.1 【<span style="background: yellow;">实验</span>】单臂路由配置</span>
            </h3>
            
            <h4>
              <span id="21011">2.10.1.1<span style="font-variant-numeric: normal; font-weight: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">     </span>拓扑图</span>
            </h4>
            
            <p>
              &nbsp;
            </p>
            
            <h4>
              <span id="21012_trunk">2.10.1.2<span style="font-variant-numeric: normal; font-weight: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">     </span>交换机trunk链路配置</span>
            </h4>
            
            <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                S-vlan-2(config)#interface gigabitEthernet 0/2
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                S-vlan-2(config-if)#switchport mode trunk
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                S-vlan-2(config-if)#switchport trunk allowed vlan all
              </p>
            </div>
            
            <h4>
              <span id="21013">2.10.1.3<span style="font-variant-numeric: normal; font-weight: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">     </span>路由器子接口配置</span>
            </h4>
            
            <p>
              <strong>fastEthernet 0/1.10</strong><strong>子接口配置</strong>
            </p>
            
            <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config)#interface fastEthernet 0/1.10
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#encapsulation dot1Q 10
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#ip address 192.168.10.254 255.255.255.0
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#no shutdown
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#exit
              </p>
            </div>
            
            <p>
              <strong>fastEthernet 0/1.20</strong><strong>子接口配置</strong>
            </p>
            
            <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config)#interface fastEthernet 0/1.20
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#encapsulation dot1Q 20
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#ip address 192.168.20.1 255.255.255.0
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                Router0(config-subif)#no shutdown
              </p>
              
              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                </div> 
                
                <h4>
                  <span id="21014">2.10.1.4<span style="font-variant-numeric: normal; font-weight: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">     </span>检查配置结果</span>
                </h4>
                
                <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                    C:\>ping 192.168.20.1
                  </p>
                  
                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                      Pinging 192.168.20.1 with 32 bytes of data:
                    </p>
                    
                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                        Reply from 192.168.20.1: bytes=32 time<1ms TTL=127
                      </p>
                      
                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                        Reply from 192.168.20.1: bytes=32 time=1ms TTL=127
                      </p>
                      
                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                        Reply from 192.168.20.1: bytes=32 time<1ms TTL=127
                      </p>
                      
                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                        Reply from 192.168.20.1: bytes=32 time<1ms TTL=127
                      </p>
                      
                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                          Ping statistics for 192.168.20.1:
                        </p>
                        
                        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                              Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
                        </p>
                        
                        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                          Approximate round trip times in milli-seconds:
                        </p>
                        
                        <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                              Minimum = 0ms, Maximum = 1ms, Average = 0ms
                        </p></div> 
                        
                        <p>
                          查看路由表
                        </p>
                        
                        <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                            Router0#show ip route
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                            Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                   D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                   N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                   E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                   i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                   * - candidate default, U - per-user static route, o - ODR
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                   P - periodic downloaded static route
                          </p>
                          
                          <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                            <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                              Gateway of last resort is not set
                            </p>
                            
                            <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                <span style="color: #e36c0a;">C    192.168.10.0/24 is directly connected, FastEthernet0/1.10</span>
                              </p>
                              
                              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                <span style="color: #e36c0a;">C    192.168.20.0/24 is directly connected, FastEthernet0/1.20</span>
                              </p>
                              
                              <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                  Router0#
                                </p></div> 
                                
                                <h1>
                                  <span id="3_STP">第3章 STP生成树</span>
                                </h1>
                                
                                <p style="margin-left: 7.1pt; text-indent: 21.0pt;">
                                  生成树协议(英语:Spanning Tree Protocol,STP),又称扩展树协议,是一基于OSI网络模型的数据链路层(第二层)通信协议,用作确保一个无环路的局域网环境。
                                </p>
                                
                                <h2>
                                  <span id="31">3.1 生成树的概念</span>
                                </h2>
                                
                                <h3>
                                  <span id="311">3.1.1 冗余拓扑</span>
                                </h3>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>冗余拓扑能够解决单点故障问题
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>冗余拓扑造成广播风暴,多帧复用,Mac地址不稳定的问题
                                </p>
                                
                                <h3>
                                  <span id="312">3.1.2 广播风暴</span>
                                </h3>
                                
                                <p style="margin-left: 45.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>HOST x发送广播帧
                                </p>
                                
                                <p style="margin-left: 45.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>交换机继续没完没了的更新广播流量
                                </p>
                                
                                <h3>
                                  <span id="313">3.1.3 多帧复制</span>
                                </h3>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>Host X 发送一个单播数据帧给 ROUTE Y
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>ROUTE Y 的MAC地址还没有被每个交换机学习到
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>ROUTE Y 接收2份相同的数据帧拷贝
                                </p>
                                
                                <h3>
                                  <span id="314_MAC">3.1.4 <span style="background: yellow;">MAC</span>表紊乱</span>
                                </h3>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>Host X 发送一个单播数据帧给 ROUTE Y
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>ROUTE Y 的MAC地址还没有被每个交换机学习到
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>switch A 和 B 在port1上学习到Host X 的MAC地址
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>到达Route Y 的数据帧被泛洪
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>Switch A和B 不正确的在Port2上学习到Host X的MAC 地址。
                                </p>
                                
                                <h3>
                                  <span id="315">3.1.5 复杂的多环路网络</span>
                                </h3>
                                
                                <p>
                                  ……
                                </p>
                                
                                <h2>
                                  <span id="32_STP">3.2 使用STP,可以达到四个效果</span>
                                </h2>
                                
                                <p style="margin-left: 24.0pt;">
                                  1、防止环路;
                                </p>
                                
                                <p style="margin-left: 24.0pt;">
                                  2、防止MAC地址震荡;
                                </p>
                                
                                <p style="margin-left: 24.0pt;">
                                  3、防止重复帧的出现;
                                </p>
                                
                                <p style="margin-left: 24.0pt;">
                                  4、防止广播风暴的出现。
                                </p>
                                
                                <h3>
                                  <span id="321_STP">3.2.1 采用生成树STP解决环路</span>
                                </h3>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>通过将特定的端口选为Blocking state,实现无环路拓扑
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>IEEE 802.1D 规定了这一行为
                                </p>
                                
                                <p style="margin-left: 42.0pt; text-indent: -21.0pt;">
                                  <span style="font-family: Wingdings;">l </span>Cisco 采用 IEEE 802.1D 的增强的私有协议生成树PVST+
                                </p>
                                
                                <h2>
                                  <span id="33_STP">3.3 STP的操作</span>
                                </h2>
                                
                                <p style="margin-left: 57.0pt; text-indent: -36.0pt;">
                                  1.<span style="font-variant-numeric: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">      </span>每个广播域选择一个<span style="background: lime;">根桥</span>root
                                </p>
                                
                                <p style="margin-left: 57.0pt; text-indent: -36.0pt;">
                                  2.<span style="font-variant-numeric: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">      </span>每个非根桥上选择一个<span style="background: lime;">根端口</span>RP
                                </p>
                                
                                <p style="margin-left: 57.0pt; text-indent: -36.0pt;">
                                  3.<span style="font-variant-numeric: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">      </span>每个段选择一个<span style="background: lime;">指定端口</span>
                                </p>
                                
                                <p style="margin-left: 57.0pt; text-indent: -36.0pt;">
                                  4.<span style="font-variant-numeric: normal; font-stretch: normal; font-size: 7pt; line-height: normal;">      </span>选择一个非指定端口
                                </p>
                                
                                <h3>
                                  <span id="331_Bridge_ID">3.3.1 每个广播域选择一个<span style="background: lime;">根桥</span> (<span style="color: #c00000; background: lime;">Bridge ID</span>)</span>
                                </h3>
                                
                                <p style="margin-left: 21.0pt;">
                                  <span style="background: lime;">BPDU</span>数据包--泛洪--选举
                                </p>
                                
                                <p>
                                        产生一个或多个非指定端口进行阻塞
                                </p>
                                
                                <p>
                                  <span style="color: #c00000;">   <span style="background: lime;">Bridge ID</span> </span>(两部分组成): 其依据是网桥优先级(bridge priority)和MAC地址组合生成的<span style="color: red;">桥</span><span style="color: red;">ID</span>
                                </p>
                                
                                <p>
                                  &nbsp;
                                </p>
                                
                                <h3>
                                  <span id="332">3.3.2 每个非根桥上选择一个<span style="background: lime;">根端口</span></span>
                                </h3>
                                
                                <p style="margin-left: 21.0pt;">
                                  根端口:具有最低的根路径的接口
                                </p>
                                
                                <p style="margin-left: 21.0pt;">
                                  要考虑的因素:
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  1. 最低的根桥ID
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  2. 最低的根路径代价
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  3. 最低的发送者根桥ID
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  4. 最低端口ID
                                </p>
                                
                                <h3>
                                  <span id="333_stpcost">3.3.3 stp路径开销<span style="color: red;">cost</span></span>
                                </h3>
                                
                                <div align="center">
                                  <table style="border-collapse: collapse; border: initial none initial;" border="1" cellspacing="0" cellpadding="0">
                                    <tr style="height: 15.6pt;">
                                      <td style="width: 134.45pt; border-top: 1pt solid #9bbb59; border-bottom: 1pt solid #9bbb59; border-left: 1pt solid #9bbb59; border-right: none; background: #9bbb59; padding: 0cm 5.4pt; height: 15.6pt;" width="179">
                                        <p style="text-align: center;" align="center">
                                          <strong><span style="color: white;">Link Speed</span></strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 184.25pt; border-top: 1pt solid #9bbb59; border-right: 1pt solid #9bbb59; border-bottom: 1pt solid #9bbb59; border-left: none; background: #9bbb59; padding: 0cm 5.4pt; height: 15.6pt;" width="246">
                                        <p style="text-align: center;" align="center">
                                          <strong><span style="color: white;">Cost</span></strong>
                                        </p>
                                        
                                        <p style="text-align: center;" align="center">
                                          <strong><span style="color: white;">(New IEEE Specification)</span></strong>
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr style="height: 15.6pt;">
                                      <td style="width: 134.45pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; background: #eaf1dd; padding: 0cm 5.4pt; height: 15.6pt;" width="179">
                                        <p style="text-align: center;" align="center">
                                          <strong>10Gb/s</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 184.25pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; background: #EAF1DD; padding: 0cm 5.4pt 0cm 5.4pt; height: 15.6pt;" width="246">
                                        <p style="text-align: center;" align="center">
                                          2
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr style="height: 15.6pt;">
                                      <td style="width: 134.45pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; padding: 0cm 5.4pt; height: 15.6pt;" width="179">
                                        <p style="text-align: center;" align="center">
                                          <strong>1Gb/s</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 184.25pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; padding: 0cm 5.4pt 0cm 5.4pt; height: 15.6pt;" width="246">
                                        <p style="text-align: center;" align="center">
                                          4
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr style="height: 15.6pt;">
                                      <td style="width: 134.45pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; background: #eaf1dd; padding: 0cm 5.4pt; height: 15.6pt;" width="179">
                                        <p style="text-align: center;" align="center">
                                          <strong>100Mb/s</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 184.25pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; background: #EAF1DD; padding: 0cm 5.4pt 0cm 5.4pt; height: 15.6pt;" width="246">
                                        <p style="text-align: center;" align="center">
                                          19
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr style="height: 15.6pt;">
                                      <td style="width: 134.45pt; border-right: 1pt solid #c2d69b; border-bottom: 1pt solid #c2d69b; border-left: 1pt solid #c2d69b; border-top: none; padding: 0cm 5.4pt; height: 15.6pt;" width="179">
                                        <p style="text-align: center;" align="center">
                                          <strong>10Mb/s</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 184.25pt; border-top: none; border-left: none; border-bottom: solid #C2D69B 1.0pt; border-right: solid #C2D69B 1.0pt; padding: 0cm 5.4pt 0cm 5.4pt; height: 15.6pt;" width="246">
                                        <p style="text-align: center;" align="center">
                                          100
                                        </p>
                                      </td>
                                    </tr>
                                  </table>
                                </div>
                                
                                <p style="text-align: center; text-indent: 21.0pt;" align="center">
                                  最短路径时cost累加,而cost时基于链路的速率的
                                </p>
                                
                                <h3>
                                  <span id="334">3.3.4 每个段选择一个指定端口</span>
                                </h3>
                                
                                <p style="margin-left: 21.0pt;">
                                  指定端口:具有最低根路径的接口
                                </p>
                                
                                <p style="margin-left: 21.0pt;">
                                  要考虑的因素:
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  1. 最低的根桥ID
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  2. 最低的根路径代价
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  3. 最低的发送者根桥ID
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  4. 最低端口ID
                                </p>
                                
                                <h2>
                                  <span id="34_root_rp_dp">3.4 【案例】root 、rp 、dp</span>
                                </h2>
                                
                                <p>
                                  比较过程:
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  1. 最低的根桥ID
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  2. 最低的根路径代价
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  3. 最低的发送者根桥ID
                                </p>
                                
                                <p style="margin-left: 81.0pt; text-indent: -18.0pt;">
                                  4. 最低端口ID
                                </p>
                                
                                <h2>
                                  <span id="35_STP">3.5 STP端口状态</span>
                                </h2>
                                
                                <div align="center">
                                  <table style="border-collapse: collapse; border: initial none initial;" border="1" cellspacing="0" cellpadding="0">
                                    <tr>
                                      <td style="width: 162.8pt; border-top: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-right: none; background: #c0504d; padding: 0cm 5.4pt;" valign="top" width="217">
                                        <p style="text-align: center;" align="center">
                                          <strong>状态</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 326pt; border-top: 1pt solid white; border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: none; background: #c0504d; padding: 0cm 5.4pt;" valign="top" width="435">
                                        <p style="text-align: center;" align="center">
                                          <strong>功能</strong>
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr>
                                      <td style="width: 162.8pt; border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #c0504d; padding: 0cm 5.4pt;" width="217">
                                        <p style="text-align: center;" align="center">
                                          <strong>阻塞(<span style="color: white;">Blocking</span></strong><strong>)</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #E5B8B7; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
                                        <p style="text-align: justify; text-justify: inter-ideograph;">
                                          这种二层LAN端口不能参与帧转发,侦听BPDU包
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr>
                                      <td style="width: 162.8pt; border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #c0504d; padding: 0cm 5.4pt;" width="217">
                                        <p style="text-align: center;" align="center">
                                          <strong>侦听(<span style="color: white;">Listening</span></strong><strong>)</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #F2DBDB; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
                                        <p style="text-align: justify; text-justify: inter-ideograph;">
                                          这是端口自阻塞状态后的第一个过渡状态。STP认为这种状态的二层LAN端口应当参与帧转发(不转发,不学习) 15s
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr>
                                      <td style="width: 162.8pt; border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #c0504d; padding: 0cm 5.4pt;" width="217">
                                        <p style="text-align: center;" align="center">
                                          <strong>学习(<span style="color: white;">Learning</span></strong><strong>)</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #E5B8B7; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
                                        <p style="text-align: justify; text-justify: inter-ideograph;">
                                          这种状态的二层LAN端口处于准备参与帧转发状态,学习MAC地址
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr>
                                      <td style="width: 162.8pt; border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #c0504d; padding: 0cm 5.4pt;" width="217">
                                        <p style="text-align: center;" align="center">
                                          <strong>转发(<span style="color: white;">Forwarding</span></strong><strong>)</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #F2DBDB; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
                                        <p style="text-align: justify; text-justify: inter-ideograph;">
                                          这种状态的二层LAN端口就可以正式转发帧了
                                        </p>
                                      </td>
                                    </tr>
                                    
                                    <tr>
                                      <td style="width: 162.8pt; border-right: 1pt solid white; border-bottom: 1pt solid white; border-left: 1pt solid white; border-top: none; background: #c0504d; padding: 0cm 5.4pt;" width="217">
                                        <p style="text-align: center;" align="center">
                                          <strong>禁止(<span style="color: white;">Disabled</span></strong><strong>)</strong>
                                        </p>
                                      </td>
                                      
                                      <td style="width: 326.0pt; border-top: none; border-left: none; border-bottom: solid white 1.0pt; border-right: solid white 1.0pt; background: #E5B8B7; padding: 0cm 5.4pt 0cm 5.4pt;" width="435">
                                        <p style="text-align: justify; text-justify: inter-ideograph;">
                                          这种状态的二层LAN端口不参与STP,不转发帧
                                        </p>
                                      </td>
                                    </tr>
                                  </table>
                                </div>
                                
                                <h2>
                                  <span id="36_stp">3.6 【实验】stp</span>
                                </h2>
                                
                                <h3>
                                  <span id="361">3.6.1 拓扑图</span>
                                </h3>
                                
                                <h3>
                                  <span id="362">3.6.2 配置命令</span>
                                </h3>
                                
                                <p style="margin-left: 7.1pt;">
                                  修改优先级
                                </p>
                                
                                <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1 (config-if)spanning-tree vlan vlan-id port-priority
                                  </p>
                                </div>
                                
                                <h3>
                                  <span id="363_STP">3.6.3 检查STP情况的命令</span>
                                </h3>
                                
                                <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1#show spanning-tree
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1#show spanning-tree active
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1#show spanning-tree detail
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1#show spanning-tree interface interface-id
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1#show spanning-tree vlan vlanid
                                  </p>
                                </div>
                                
                                <p>
                                  &nbsp;
                                </p>
                                
                                <div style="border: solid #404040 4.5pt; padding: 1.0pt 4.0pt 1.0pt 4.0pt; background: #404040;">
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    S-STP-1(config)#do sh spann
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    VLAN0001
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                      Spanning tree enabled protocol ieee
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                      Root ID    Priority    32769
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                 Address     0001.C944.E360
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                <span style="color: #e36c0a;"> This bridge is the root</span>
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                 Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec
                                  </p>
                                  
                                  <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                        Bridge ID  Priority    32769  (priority 32768 sys-id-ext 1)
                                    </p>
                                    
                                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                   Address     0001.C944.E360
                                    </p>
                                    
                                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                   Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec
                                    </p>
                                    
                                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                                   Aging Time  20
                                    </p>
                                    
                                    <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                        Interface        Role Sts Cost      Prio.Nbr Type
                                      </p>
                                      
                                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                        ---------------- ---- --- --------- -------- --------------------------------
                                      </p>
                                      
                                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                        Fa0/1            Desg FWD 19        128.1    P2p
                                      </p>
                                      
                                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                        Gi0/1            Desg FWD 4         128.25   P2p
                                      </p>
                                      
                                      <p style="text-indent: 15.75pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;">
                                        Gi0/2            Desg FWD 4         128.26   P2p
                                      </p></div> 
                                      
                                      <div id="toc_container" class="toc_white have_bullets">
                                        <ul class="toc_list">
                                          <li>
                                            <a href="#1">第1章 交换基础</a><ul>
                                              <li>
                                                <a href="#11">1.1 园区网分层结构</a>
                                              </li>
                                              <li>
                                                <a href="#12">1.2 交换机的主要功能</a>
                                              </li>
                                              <li>
                                                <a href="#13_MAC">1.3 MAC地址</a>
                                              </li>
                                              <li>
                                                <a href="#14">1.4 交换寻址</a>
                                              </li>
                                            </ul>
                                          </li>
                                          
                                          <li>
                                            <a href="#2_VLAN">第2章 VLAN 虚拟局域网</a><ul>
                                              <li>
                                                <a href="#21_vlan">2.1 vlan概述</a>
                                              </li>
                                              <li>
                                                <a href="#22_vlan">2.2 vlan的成员模式</a>
                                              </li>
                                              <li>
                                                <a href="#23_trunk">2.3 trunk干道</a><ul>
                                                  <li>
                                                    <a href="#231_ISL">2.3.1 ISL封装协议(使用较少)</a>
                                                  </li>
                                                  <li>
                                                    <a href="#232_dot1q8011q">2.3.2 dot1q协议(801.1q)</a>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#24_VLAN">2.4 VLAN的特点</a>
                                              </li>
                                              <li>
                                                <a href="#25_ciscovlan">2.5 cisco上vlan范围</a>
                                              </li>
                                              <li>
                                                <a href="#26_VTP_VLAN_Trunking_Protocol">2.6 VTP (VLAN Trunking Protocol)</a><ul>
                                                  <li>
                                                    <a href="#261_vlan">2.6.1 vlan使用过程</a>
                                                  </li>
                                                  <li>
                                                    <a href="#262_vtp">2.6.2 vtp三种模式</a>
                                                  </li>
                                                  <li>
                                                    <a href="#263_VTP">2.6.3 VTP的运作</a>
                                                  </li>
                                                  <li>
                                                    <a href="#264_VTP_Pruning">2.6.4 VTP的修剪 Pruning</a><ul>
                                                      <li>
                                                        <a href="#2641vlan">2.6.4.1 允许所有vlan通过会有什么缺点呢?</a>
                                                      </li>
                                                    </ul>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#27_VLAN">2.7 VLAN基本配置</a><ul>
                                                  <li>
                                                    <a href="#271_VLAN">2.7.1 创建VLAN信息</a>
                                                  </li>
                                                  <li>
                                                    <a href="#272_vlan">2.7.2 将端口划入特定的vlan</a>
                                                  </li>
                                                  <li>
                                                    <a href="#273_Trunk">2.7.3 配置Trunk封装方式</a>
                                                  </li>
                                                  <li>
                                                    <a href="#274">2.7.4 开启端口</a>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#28_VTP">2.8 VTP的基本配置</a><ul>
                                                  <li>
                                                    <a href="#281">2.8.1 注意:</a>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#29_vlan">2.9 【实验】vlan</a><ul>
                                                  <li>
                                                    <a href="#291">2.9.1 拓扑图</a>
                                                  </li>
                                                  <li>
                                                    <a href="#292">2.9.2 交换机配置</a>
                                                  </li>
                                                  <li>
                                                    <a href="#293_vlan">2.9.3 查看vlan信息</a><ul>
                                                      <li>
                                                        <a href="#2931S-vlan-1">2.9.3.1 S-vlan-1信息</a>
                                                      </li>
                                                      <li>
                                                        <a href="#2932S-vlan-2">2.9.3.2 S-vlan-2信息</a>
                                                      </li>
                                                      <li>
                                                        <a href="#2933trunk">2.9.3.3 查看trunk信息</a>
                                                      </li>
                                                    </ul>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#210">2.10 单臂路由</a><ul>
                                                  <li>
                                                    <a href="#2101">2.10.1 【实验】单臂路由配置</a><ul>
                                                      <li>
                                                        <a href="#21011">2.10.1.1     拓扑图</a>
                                                      </li>
                                                      <li>
                                                        <a href="#21012_trunk">2.10.1.2     交换机trunk链路配置</a>
                                                      </li>
                                                      <li>
                                                        <a href="#21013">2.10.1.3     路由器子接口配置</a>
                                                      </li>
                                                      <li>
                                                        <a href="#21014">2.10.1.4     检查配置结果</a>
                                                      </li>
                                                    </ul>
                                                  </li>
                                                </ul>
                                              </li>
                                            </ul>
                                          </li>
                                          
                                          <li>
                                            <a href="#3_STP">第3章 STP生成树</a><ul>
                                              <li>
                                                <a href="#31">3.1 生成树的概念</a><ul>
                                                  <li>
                                                    <a href="#311">3.1.1 冗余拓扑</a>
                                                  </li>
                                                  <li>
                                                    <a href="#312">3.1.2 广播风暴</a>
                                                  </li>
                                                  <li>
                                                    <a href="#313">3.1.3 多帧复制</a>
                                                  </li>
                                                  <li>
                                                    <a href="#314_MAC">3.1.4 MAC表紊乱</a>
                                                  </li>
                                                  <li>
                                                    <a href="#315">3.1.5 复杂的多环路网络</a>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#32_STP">3.2 使用STP,可以达到四个效果</a><ul>
                                                  <li>
                                                    <a href="#321_STP">3.2.1 采用生成树STP解决环路</a>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#33_STP">3.3 STP的操作</a><ul>
                                                  <li>
                                                    <a href="#331_Bridge_ID">3.3.1 每个广播域选择一个根桥 (Bridge ID)</a>
                                                  </li>
                                                  <li>
                                                    <a href="#332">3.3.2 每个非根桥上选择一个根端口</a>
                                                  </li>
                                                  <li>
                                                    <a href="#333_stpcost">3.3.3 stp路径开销cost</a>
                                                  </li>
                                                  <li>
                                                    <a href="#334">3.3.4 每个段选择一个指定端口</a>
                                                  </li>
                                                </ul>
                                              </li>
                                              
                                              <li>
                                                <a href="#34_root_rp_dp">3.4 【案例】root 、rp 、dp</a>
                                              </li>
                                              <li>
                                                <a href="#35_STP">3.5 STP端口状态</a>
                                              </li>
                                              <li>
                                                <a href="#36_stp">3.6 【实验】stp</a><ul>
                                                  <li>
                                                    <a href="#361">3.6.1 拓扑图</a>
                                                  </li>
                                                  <li>
                                                    <a href="#362">3.6.2 配置命令</a>
                                                  </li>
                                                  <li>
                                                    <a href="#363_STP">3.6.3 检查STP情况的命令</a>
                                                  </li>
                                                </ul>
                                              </li>
                                            </ul>
                                          </li>
                                        </ul>
                                      </div>