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switch的用法和短语
switch的用法和短语概述：在英语中，Switch是一个非常常用的动词，它有着多种不同的用法和短语。
本文将介绍Switch的几种用法，并提供相关短语的例句和解释。
一、交换或转变（Transfer or Change）1. Switch (from...) to..."Switch (from...) to..." 是指从一种状态或行为转变到另外一种状态或行为。
例如：- I decided to switch from a vegetarian diet to a vegan diet for ethical reasons.- She switched from ballet to hip-hop dance.2. Switch (sth) with..."Switch something with..." 表示与某物进行交换。
例如：- Can I switch seats with you so that I can sit next to my friend?- He switched his old phone with the latest model.3. Switch on/off"Switch on/off" 是打开或关闭某个设备或电器时使用的短语。
例如：- Don't forget to switch off the lights when you leave the room.- She switched on her computer and started working on her assignment.4. Switch between..."Switch between..." 意味着在两个或多个选项之间进行切换。
例如：- You can switch between different languages on this website.- He likes to switch between coffee and tea depending on his mood.二、改变观点（Change Perspective）1. Switch sides/positions/roles"Switch sides/positions/roles" 意味着改变立场、职位或角色。
STP 生成树协议配置
实验八生成树配置实验1【实验名称】生成树协议STP【实验目的】理解生成树协议STP的配置及原理。
【背景描述】某学校为了开展计算机教学和网络办公，建立了一个计算机教室和一个校办公区，这两处的计算机网络通过两台交换机互连组成内部校园网，为了提高网络的可靠性，网络管理员用2条链路将交换机互连，现要在交换机上做适当配置，使网络避免环路。
本实验以2台S2126G交换机为例，2台交换机分别命名为SwitchA, SwitchB。
PC1与PC2在同一个网段，假设IP地址分别为192.168.0.137，192.168.0.136，网络掩码为255.255.255.0 。
【实现功能】使网络在有冗余链路的情况下避免环路的产生，避免广播风暴等。
【实验拓扑】F0/3F0/3【实验设备】S2126G（2台）【实验步骤】第一步：在每台交换机上开启生成树协议．例如对SwitchA做如下配置：SwitchA#configure terminal ！进入全局配置模式SwitchA(config)#spanning-tree ！开启生成树协议SwitchA(config)#end验证测试：验证生成树协议已经开启SwitchA#show spanning-tree ！显示交换机生成树的状态StpVersion : MSTPSysStpStatus : EnabledBaseNumPorts : 24MaxAge : 20HelloTime : 2ForwardDelay : 15BridgeMaxAge : 20BridgeHelloTime : 2BridgeForwardDelay : 15MaxHops : 20TxHoldCount : 3PathCostMethod : LongBPDUGuard : DisabledBPDUFilter : Disabled###### MST 0 vlans mapped : AllBridgeAddr : 00d0.f8ef.9e89Priority : 32768TimeSinceTopologyChange : 0d:0h:0m:8sTopologyChanges : 0DesignatedRoot : 800000D0F8EF9D09RootCost : 200000RootPort : Fa0/1CistRegionRoot : 800000D0F8EF9E89CistPathCost : 0SwitchA#show spanning-tree interface fastthernet 0/1 ！显示交换机接口fastthernet 0/1的状态PortAdminPortfast : DisabledPortOperPortfast : DisabledPortAdminLinkType : autoPortOperLinkType : point-to-pointPortBPDUGuard: DisabledPortBPDUFilter: Disabled###### MST 0 vlans mapped : AllPortState : forwarding ！显示接口fastthernet 0/1处于转发（forwarding）状态PortPriority : 128PortDesignatedRoot : 800000D0F8EF9D09PortDesignatedCost : 0PortDesignatedBridge : 800000D0F8EF9D09PortDesignatedPort : 8001PortForwardTransitions : 1PortAdminPathCost : 0PortOperPathCost : 200000PortRole : rootPort第二步：设置生成树模式SwitchA(config)#spanning-tree mode stp ！设置生成树模式为STP (802.1D)验证测试：验证生成树协模式为802.1DSwitchA#show spanning-treeStpVersion : STPSysStpStatus : EnabledBaseNumPorts : 24MaxAge : 20HelloTime : 2ForwardDelay : 15BridgeMaxAge : 20BridgeHelloTime : 2BridgeForwardDelay : 15MaxHops : 20TxHoldCount : 3PathCostMethod : LongBPDUGuard : DisabledBPDUFilter : DisabledBridgeAddr : 00d0.f8ef.9e89Priority : 32768TimeSinceTopologyChange : 0d:0h:7m:0sTopologyChanges : 0DesignatedRoot : 800000D0F8EF9D09RootCost : 200000RootPort : Fa0/1第三步：设置交换机的优先级SwitchA(config)#spanning-tree priority 4096 ！设置交换机SwitchA的优先级为4096, 数值最小的交换机为根交换机（也称根桥），交换机SwitchB的优先级采用默认优先级（32768），因此SwitchA将成为根交换机。
H3C交换机_典型配置举例-6W100-以太网链路聚合典型配置举例
1 链路聚合典型配置举例······················································································································· 1-1 1.1 简介 ···················································································································································1-1 1.2 二层链路聚合配置举例 ······················································································································1-1 1.2.1 适用产品和版本 ······················································································································1-1 1.2.2 组网需求 ·································································································································1-1 1.2.3 配置思路 ·································································································································1-1 1.2.4 配置注意事项 ··························································································································1-2 1.2.5 配置步骤 ·································································································································1-2 1.2.6 验证配置 ································································································································1-3 1.2.7 配置文件 ·································································································································1-4 1.3 二层聚合负载分担配置举例···············································································································1-5 1.3.1 适用产品和版本 ······················································································································1-5 1.3.2 组网需求 ·································································································································1-5 1.3.3 配置思路 ·································································································································1-6 1.3.4 配置注意事项 ··························································································································1-6 1.3.5 配置步骤 ·································································································································1-6 1.3.6 验证配置 ·································································································································1-7 1.3.7 配置文件 ·································································································································1-8 1.4 三层链路聚合配置举例 ······················································································································1-9 1.4.1 适用产品和版本 ······················································································································1-9 1.4.2 组网需求 ·······························································································································1-10 1.4.3 配置思路 ·······························································································································1-10 1.4.4 配置注意事项 ························································································································1-10 1.4.5 配置步骤 ·······························································································································1-10 1.4.6 验证配置 ·······························································································································1-11 1.4.7 配置文件 ·······························································································································1-12
NQA配置指导（华为、H3C）
NQA配置指导（华为、H3C）1、H3C NQA、静态路由联动# 创建管理员名为admin、操作标签为test的NQA测试组[SwitchA] nqa entry admin test# 配置测试类型为ICMP-echo[SwitchA-nqa-admin-test] type icmp-echo# 配置测试的⽬的地址为10.2.1.4，下⼀跳地址为10.1.1.2[SwitchA-nqa-admin-test-icmp-echo] destination ip 10.2.1.4[SwitchA-nqa-admin-test-icmp-echo] next-hop 10.1.1.2# 配置测试频率为100ms[SwitchA-nqa-admin-test-icmp-echo] frequency 100# 配置可选参数：⼀次NQA测试中探测的次数为10，探测的超时时间为500毫秒，测试组连续两次测试开始时间的时间间隔为5000毫秒。
[SwitchA-nqa-admin-test-icmp-echo] probe count 10[SwitchA-nqa-admin-test-icmp-echo] probe timeout 500[SwitchA-nqa-admin-test-icmp-echo] frequency 5000# 开启NQA历史记录保存功能，并配置⼀个测试组中能够保存的最⼤历史记录个数为10[SwitchA-nqa-admin-test-icmp-echo] history-record enable[SwitchA-nqa-admin-test-icmp-echo] history-record number 10# 配置联动项1（连续失败5次触发联动）[SwitchA-nqa-admin-test-icmp-echo] reaction 1 checked-element probe-fail threshold-type consecutive 5 action-type trigger-only# 启动探测[SwitchA] nqa schedule admin test start-time now lifetime forever# 配置Track项1，关联NQA测试组（管理员为admin，操作标签为test）的联动项1[SwitchA] track 1 nqa entry admin test reaction 1# 显⽰ICMP-echo测试中最后⼀次测试的结果[SwitchA] display nqa result admin test# 显⽰ICMP-echo测试的统计结果[SwitchA] display nqa statistics admin test# 显⽰ICMP-echo测试的历史记录[SwitchA] display nqa history admin test# 显⽰Switch A上Track项的信息[SwitchA] display track all# 配置静态路由关联track 1[SwitchA] ip route-static 30.1.1.0 24 10.1.1.2 track 12、H3C NQA、VRRP联动# 在VLAN接⼝1下配置VRRP[SwitchA] interface vlan-interface 1# 创建备份组1，并配置备份组1的虚拟IP地址为10.1.1.10[SwitchA-Vlan-interface2] vrrp vrid 1 virtual-ip 10.1.1.10# 设置Switch A在备份组1中的优先级为110。
antd a-switch 用法
一、概述antd（AntDesign）是一款高质量的ReactUI组件库，它提供了丰富的组件供开发者使用。
a-switch组件是antd中的一个重要组件，用于创建切换开关功能。
本文将详细介绍a-switch的用法。
二、基本用法在使用a-switch组件之前，需要先确保已经正确引入了antd 库。
然后在需要使用a-switch的地方，只需要在组件容器中添加a-switch组件即可。
基本语法如下：```jsx<a-switch/>或<a-switchvalue={true}/>或<a-switchvalue={false}/>```其中，value属性用于设置开关的状态，true表示开启，false 表示关闭。
三、开关状态改变事件a-switch组件提供了change事件，用于监听开关状态的变化。
当开关状态发生变化时，会触发change事件，并传递当前开关状态作为参数。
```jsx<a-switchonChange={handleChange}/>```其中，handleChange是一个函数，用于处理开关状态变化时的逻辑。
函数接收一个参数，表示当前开关状态（true表示开启，false 表示关闭）。
四、开关状态展示样式a-switch组件提供了丰富的样式选项，可以自定义开关的外观和颜色等。
可以使用style属性来设置样式，也可以使用CSS样式来覆盖默认样式。
```jsx<a-switchstyle={{backgroundColor:'blue',color:'white'}}/> ```或者使用CSS来覆盖默认样式：```css.ant-switch-wrapper{/*yourstyleshere*/}```五、禁用状态a-switch组件提供了disabled属性，用于设置开关的禁用状态。
当开关被禁用时，它不会响应任何交互事件，也不会显示任何视觉反馈。
c语言switch中case后范围
c语言switch中case后范围一、概述在C语言中，switch语句是一种多分支选择结构，它根据表达式的值跳转到不同的代码块。
每个case标签后面可以跟一个常量表达式或范围表达式。
本文将着重介绍switch中case后范围的使用。
二、case后常量表达式在C语言中，case标签后面可以跟一个常量表达式。
当switch语句执行时，会比较表达式的值和每个case标签的值是否相等，如果相等，则执行该case标签对应的代码块。
例如：```int a = 1;switch(a){case 1:printf("a is 1\n");break;case 2:printf("a is 2\n");break;default:printf("a is not 1 or 2\n");}```上述代码中，a的值为1，因此会执行第一个case标签对应的代码块，并输出"a is 1"。
三、case后范围表达式除了常量表达式外，C语言还支持在case标签后面使用范围表达式。
范围表达式由两个常量组成，用冒号(:)分隔开来表示一个区间。
例如：```int b = 3;switch(b){case 1 ... 3:printf("b is between 1 and 3\n");break;case 4 ... 6:printf("b is between 4 and 6\n");break;default:printf("b is not between 1 and 6\n");}```上述代码中，b的值为3，因此会执行第一个case标签对应的代码块，并输出"b is between 1 and 3"。
四、范围表达式的注意事项使用范围表达式时需要注意以下几点：1. 范围表达式只能在C99及以上版本中使用。
华三交换机命令.docx
H3C 交换机配置命令大全1、system-view 进入系统视图模式2、sysname 为设备命名3、display current-configuration 当前配置情况4、language-mode Chinese|English 中英文切换5、interface Ethernet 1/0/1 进入以太网端口视图6、port link-type Access|Trunk|Hybrid 设置端口访问模式7、undo shutdown 打开以太网端口8、shutdown 关闭以太网端口9、quit 退出当前视图模式10、vlan 10 创建VLAN 10 并进入VLAN 10 的视图模式11、port access vlan 10 在端口模式下将当前端口加入到vlan 10 中12、port E1/0/2 to E1/0/5 在VLAN 模式下将指定端口加入到当前vlan中13、port trunk permit vlan all 允许所有的vlan 通过H3C 路由器1 、system-view 进入系统视图模式2、sysname R1 为设备命名为R13、display ip routing-table 显示当前路由表4、language-mode Chinese|English 中英文切换5、interface Ethernet 0/0 进入以太网端口视图6、ip address 192.168.1.1 255.255.255.0 配置IP 地址和子网掩码7、undo shutdown 打开以太网端口8、shutdown 关闭以太网端口9、quit 退出当前视图模式10、ip route-static 192.168.2.0 255.255.255.0 192.168.12.2 description To.R2 配置静态路由11、ip route-static 0.0.0.0 0.0.0.0 192.168.12.2 description To.R2 配置默认的路由H3C S3100 SwitchH3C S3600 SwitchH3C MSR 20-20 Router1、调整超级终端的显示字号；2、捕获超级终端操作命令行，以备日后查对；3、language-mode Chinese|English 中英文切换；4、复制命令到超级终端命令行，粘贴到主机；5、交换机清除配置:<H3C>reset save ；<H3C>reboot ；6、路由器、交换机配置时不能掉电，连通测试前一定要检查网络的连通性，不要犯最低级的错误。
华三（H3C）交换机配置跨交换机间VLAN的通信
一组网需求：1．SwitchA与Switc hB用tru nk互连，相同VLAN的PC之间可以互访，不同VLAN的PC之间禁止互访；2．PC1与PC2之间在不同V LAN，通过设置上层三层交换机Sw itchB的VLAN接口10的IP地址为10.1.1.254/24，VLAN接口20的IP地址为20.1.1.254/24可以实现V LAN间的互访。
二组网图：1．VLAN内互访，VLAN间禁访一、实现VLAN内互访VLAN间禁访配置过程SwitchA相关配置：1．创建（进入）VLAN10，将E0/1加入到VLA N10[SwitchA]vlan 10[SwitchA-vlan10]port Etherne t 0/12．创建（进入）VLAN20，将E0/2加入到VLA N20[SwitchA]vlan 20[SwitchA-vlan20]port Etherne t 0/23．将端口G1/1配置为Tru nk端口，并允许VLAN10和VLA N20通过[SwitchA]interfa ce Gigabit Ethern et 1/1[SwitchA-Gigabit Ethern et1/1]port link-type trunk[SwitchA-Gigabit Ethern et1/1]port trunk permitvlan 10 20SwitchB相关配置：1．创建（进入）VLAN10，将E0/10加入到VL AN10[SwitchB]vlan 10[SwitchB-vlan10]port Etherne t 0/102．创建（进入）VLAN20，将E0/20加入到VL AN20[SwitchB]vlan 20[SwitchB-vlan20]port Etherne t 0/203．将端口G1/1配置为Tru nk端口，并允许VLAN10和VLA N20通过[SwitchB]interfa ce Gigabit Ethern et 1/1[SwitchB-Gigabit Ethern et1/1]port link-type trunk[SwitchB-Gigabit Ethern et1/1]port trunk permitvlan 10 20二、通过三层交换机实现VLAN间互访通过三层交换机实现VLAN间互访的配置SwitchA相关配置：1．创建（进入）VLAN10，将E0/1加入到VLA N10[SwitchA]vlan 10[SwitchA-vlan10]port Etherne t 0/12．创建（进入）VLAN20，将E0/2加入到VLA N20[SwitchA]vlan 20[SwitchA-vlan20]port Etherne t 0/23．将端口G1/1配置为Tru nk端口，并允许VLAN10和VLA N20通过[SwitchA]interfa ce Gigabit Ethern et 1/1[SwitchA-Gigabit Ethern et1/1]port link-type trunk[SwitchA-Gigabit Ethern et1/1]port trunk permitvlan 10 20SwitchB相关配置：1．创建VLAN10[SwitchB]vlan 102．设置VLAN10的虚接口地址[SwitchB]interfa ce vlan 10[SwitchB-int-vlan10]ip address 10.1.1.254 255.255.255.03．创建VLAN20[SwitchB]vlan 204．设置VLAN20的虚接口地址[SwitchB]interfa ce vlan 20[SwitchB-int-vlan20]ip address 20.1.1.254 255.255.255.05．将端口G1/1配置为Tru nk端口，并允许VLAN10和VLA N20通过[SwitchA]interfa ce Gigabit Ethern et 1/1[SwitchA-Gigabit Ethern et1/1]port link-type trunk[SwitchA-Gigabit Ethern et1/1]port trunk permitvlan 10 20。
CKSWITCHES A-108 按钮说明书
Specifications and dimensions subject to changeP u s h b u t t o nFeatures/Benefits • I P67 sealed• 1,000,000 life cycle• Illumination / non-illumination • M ultiple colored caps • T hreaded or snap-in mounting • C aps available separately • R oHS compliantTypical Applications• H arsh environments • O ff-Road • I ndustrial • M edical • T ransportation • J oystick control modules • G aming • M ilitarySpecificationsFUNCTION: SPST Momentary CONTACT ARRANGEMENT: N.O.MOUNTING TYPE: Snap-in (no panel seal)Threaded body (hex nut, lock washer, and panel seal gasket provided)Torque spec for threaded body: Do not exceed 8-9 in-lbs (0.9-1.0 N.m)MechanicalOPERATING LIFE: 1,000,000 cycles TOTAL TRAVEL: 2.1 ± 0.2 mmOPERATING POINT 1.55 ± 0.25 mm OVER TRAVEL: 0.6 min.OPERATING FORCE: 4N ± 1N standard configuration; other forceoption 2N ± 0.5NVIBRATION: 10-500 Hz 10g Max SHOCK: 60g 11ms sawtooth waveElectricalCONTACT RATING: 200mA @ 24 V DC resistive (500,000 cycles) 100mA @ 50 V DC resistive (500,000 cycles) 400mA @ 32 V AC resistive (500,000 cycles) 125mA @ 125 V AC resistive (1,000,000 cycles)DIELECTRIC STRENGTH: 1000 V AC min.INSULATION RESISTANCE: 1 G Ω @ 500 VDCINITIAL CONTACT RESISTANCE 50 mΩ max (without wire leads)BOUNCE TIME: <5 msMaterialsHOUSING: PBTBASE: PBT CAP: PBT ACTUATOR: Illuminated: Clear polycarbonate Non-illuminated: PBT INTERNAL SEAL: Silicone rubberTERMINALS: Copper alloy, gold over silver platingMOVABLE CONTACT: Copper alloy, gold over silver plating TERMINAL SEAL: EpoxyWIRE LEADS: UL1569 Black 22 AWGOperating EnvironmentOPERATING TEMPERATURE: -40˚C to 85˚C (+105˚C non-illuminated)ESD PROTECTION: 20 KV min.Process EnvironmentSEALING: IP67 for threaded bodyIP65 for snap-in version (no panel seal)NOTE: Specifications and materials listed above are for switches with standard options. For information on specific and custom switches, please contact Customer Service.Build-A-SwitchTo order, simply select desired option from each category and place in the appropriate box.Designation AP AP SeriesAP SeriesIndustrial Pushbutton SwitchOperating Force 2 2 Newtons 4 4 NewtonsActuator StyleD Dome / Convex C ConcaveE Extended Dome N NoneActuator Color0 No Cap 2 Black 3 Red 4 Orange 5 Yellow 6 Green 7 Blue 9 GrayIllumination00 No LED*01 Super White 02 Bi-color; Red (Green)03 Red 05 Amber 06 Green 07 Super Blue 08 Bi-color; Amber (Green)* No LED available in short body onlyContact Material B Gold Terminal SealE EpoxyAll models are epoxy sealedTermination Z Solder Lug W 12” Wire Leads 22 AWG C*** PC TerminalsBushing Style**S** Snap-in plastic T Threaded plastic** No panel seal option***PC terminals not available with illuminationContact Customer Service for additional hardware options.Please contact Customer Service for additional colors and paint / laser etched button options.28 Jul 21OPTION CODEACTUATOR COLORNo Cap2 Black3 Red4 Orange 5Yellow 6 Green 7 Blue9GrayPushbuttonAP SeriesOPTIO N CODE OPERATING FORCE22 N, 200 g 44 N, 400 gAP SeriesIndustrial Pushbutton Switch*LED FORWARD CURRENT: 20 mALED FORWARD VOLTAGE: see chart above 07LED Super Blue08LED Bi-Color – Amber (Green)02LED Bi-Color – Red (Green)OPTION CODEILLUMINATIONTYPE00Model without illumination01LED Super White 03LED Red 05LED Amber 06LED Green 800 1,500 101010 20TYPICAL INTENSITY* MI N MAX35 50(mcd) 4,000 5,000 4 8 35 50PEAKWAVELENGTH(nm)N/A700 610 585/565565 N/A470635/565N/AVf Forward Voltage2.0 2.0 2.02.03.5 3.82.0P u s h b u t t o nPushbutton AP SeriesDimensions are shown: mm (inches)Specifications and dimensions subject to changeP u s h b u t t o nThird AngleAP SeriesIndustrial Pushbutton SwitchHARDWAREProjectionLOCK WASHERPart Number 647D00A47B GOLDOPTIO N CODE CONTACT MATERIALBGoldE EPOXYAll models are epoxy sealedPANEL SEALPart Number 655D0000028 Jul 21AP SeriesDOME481DXX000 = NO HOLE481DXX001 = HOLEDimensions are shown: Inches (mm)Specifications and dimensions subject to changeP u s h b u t t o nFeatures/Benefits • I P67 sealed• 1,000,000 life cycle • Illumination • T hreaded or snap-in mounting • R oHS compliantTypical Applications• H arsh environments • O ff-Road • I ndustrial • M edical • T ransportation • J oystick control modules • G aming • M ilitarySpecificationsFUNCTION: SPST Momentary CONTACT ARRANGEMENT: N.O.MOUNTING TYPE: Snap-in (no panel seal)Threaded body (hex nut, lock washer, and panel seal gasket provided)Torque spec for threaded body: Do not exceed 8-9 in-lbs (0.9-1.0 N.m)MechanicalOPERATING LIFE: 1,000,000 cycles TOTAL TRAVEL: 2.1 ± 0.2 mmOPERATING POINT 1.55 ± 0.25 mm OVER TRAVEL: 0.6 min.OPERATING FORCE: 4N ± 1N standard configuration; other forceoption 2N ± 0.5NVIBRATION: 10-500 Hz 10g Max SHOCK: 60g 11ms sawtooth waveElectricalCONTACT RATING: 200mA @ 24 V DC resistive (500,000 cycles) 100mA @ 50 V DC resistive (500,000 cycles) 400mA @ 32 V AC resistive (500,000 cycles) 125mA @ 125 V AC resistive (1,000,000 cycles)DIELECTRIC STRENGTH: 1000 V AC min.INSULATION RESISTANCE: 1 G Ω @ 500 VDCINITIAL CONTACT RESISTANCE 50 mΩ max (without wire leads)BOUNCE TIME: <5 msMaterialsHOUSING: PBTBASE: PBTCAP: Painted polycarbonate ACTUATOR: Illuminated: Clear polycarbonate INTERNAL SEAL: Silicone rubberTERMINALS: Copper alloy, gold over silver platingMOVABLE CONTACT: Copper alloy, gold over silver plating TERMINAL SEAL: EpoxyWIRE LEADS: UL1569 Black 22 AWGOperating EnvironmentOPERATING TEMPERATURE: -40˚C to 85˚C ESD PROTECTION: 20 KV min.Process EnvironmentSEALING: IP67 for threaded bodyIP65 for snap-in version (no panel seal)NOTE:Specifications and materials listed above are for switches with standard options. For information on specific and custom switches, please contact Customer Service.Build-A-SwitchTo order, simply select desired option from each category and place in the appropriate box.DesignationAPB APB SeriesAPB SeriesBacklit Pushbutton SwitchOperating Force 2 2 Newtons 4 4 NewtonsCapEExtended Dome (600E)Illumination01 Super White 07 Super BlueContact MaterialBGoldTerminal Seal E EpoxyTerminationZ Solder Lug W 12” Wire Leads 22 AWG Bushing StyleS Snap-in plastic T Threaded plasticCap Symbol000 Painted black over white without symbol*001 Plus 002 Locked 003 Engine stop 004 Park brake release 005 Engine start 006 Fast 007 Slow 008 Unlocked 009 Rock shaft lower 010 Minus* cap painted black over white toallow customer laser etching28 Jul 21Dimensions are shown: Inches (mm)Specifications and dimensions subject to changePushbuttonABA27,95 REF [1.100]20,35[.801]1,5[.059]7,6[.299]17,4[.685]2X 7,5[.295]2X 4[.157]2X 1,81[.071]12,35[.486]5,7[.224]DOWN POSITION0,85[.033]PANEL THICKNESS DIM A (0.05 MM)DIM B (0.05 MM)1 MM [0.039 IN]13.70 MM [0.539 IN]13.00 MM [0.512 IN]2 MM [0.079 IN]13.80 MM [0.539 IN]13.00 MM [0.512 IN]3 MM [0.118 IN]13.90 MM [0.547 IN]13.10 MM [0.516 IN]THREADED BODYMIN PANEL THICKNESS 1 MM13.70 MM [0.539 IN]13.00 MM [0.512 IN]12SPST-NO-DBELECTRICAL SCHEMATIC34SEE SCHEMATICA 0.1 MM MIN CHAMFER ON THE LEADING EDGE OF MOUNTING HOLE IS RECOMMENDED FOR SNAP-IN VERSION.M13 X 1.25-6gTHREADEDPANEL CUTOUTSNAP-IN1243APB SeriesBacklit Pushbutton SwitchThird Angle Projection28 Jul 21Dimensions are shown: Inches (mm)Specifications and dimensions subject to changeh b u t t o nAPB SeriesBacklit Pushbutton SwitchW 12” WIRE LEADSZ SOLDER LUGB GOLDOPTIO N CODE CONTACT MATERIALBGoldE EPOXYAll models are epoxy sealedThird AngleProjection28 Jul 21LOCK WASHERPart Number 647D00A47APB SeriesBacklit Pushbutton SwitchHARDWARE。
switch的用法和短语 (2)
switch的用法和短语一、Switch的用法解析在英语学习中，switch是一个重要而常用的单词，它有多个意思和用法。
本文将着重介绍switch作为动词和名词的用法，并深入讨论与switch相关的常见短语。
二、Switch作为动词的用法1. 转换/切换Switch作为动词最常见的意思是“转换”或“切换”。
例如，我们可以使用switch来描述在两个选项之间进行转变。
比如： "She switched from studying chemistry to physics."（她从学习化学转换到了物理）2. 打开/关闭另一种常见的用法是指“打开”或“关闭”。
这通常与电力、灯光、设备等相关。
例如： "Don't forget to switch off the lights when you leave." （离开时别忘了关灯）3. 让渡/交接除此之外，switch也可表示“让渡”或“交易”。
这通常用于商业或管理场景。
例如： "He plans to switch his responsibilities to his colleagues while he's on vacation."（他计划在休假期间将职责让给同事）4. 变更/改变还有一种含义是指“变更”或“改变”，主要涉及行为、立场、观点等方面。
例如："She switched her major from engineering to literature." （她改变了主修专业，从工程转向文学）三、Switch常见短语解析1. Switch on/offSwitch on和switch off分别表示“打开”和“关闭”，主要用于电力或设备相关的情景。
例如： "I always switch off my phone during meetings to avoid distractions."（我在会议期间总是关掉手机以避免分散注意力）2. Switch between/toSwitch between和switch to都指“在两个选项之间切换”，只是to后通常接一个具体的选项。
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1、switch a 、switch b选用两台锐捷的s5750 ；switch c 、shwich d 选
用锐捷的 s3750和s3760
2、全网共有两个业务vlan ,为 vlan 10 、vlan 20
3、Switch a 、switch b 都分别对两vlan起用两vrrp组，实现两组的业务的
负载分担和备份。
4、Switch a、switch b、switch c、switch d 都起用 mstp多生成数协议，并
且所有设备都属于同一个mst域，且实例映射一致（vlan 10映射实例1、
vlan 20映射实例2 其他vlan映射默认实例0）。
5、Vlan 10业务以switch a为根桥； vlan 20业务以switch b为根桥；实现
阻断网络环路，并能实现不同vlan数据流负载分担功能。
1. RSTP和MSTP配合为什么有问题
原因：由于RSTP/MSTP的指定端口快速迁移机制，即接收到下游的agreement报文才
能进行快速迁移。引发这样的问题：上游桥运行RSTP，下游运行MSTP，此时，RSTP不
向下游发agreement报文，MSTP的根端口没有接收到agreement报文，则表示MSTP没有
同步，这就意味着根端口不向上游RSTP指定端口发agreement。所以，MSTP域内的agreement
被抑制，上游RSTP指定端口只能在2倍的Forward Delay延时后Forwarding。
解决方法：将运行MSTP协议的桥作为上游，运行RSTP的桥做下游。因为RSTP的同
步不要求根端口接收到上游的agreement，所以在这种情况下上游MSTP指定端口可以接收
到下游RSTP根端口发送的agreement，就可以快速迁移了。
（1）连接终端的端口使能了STP，但是没有配置边缘端口，当终端发生重启等情况导
致该端口发生链路状态变化时，该端口会产生TC报文并向整个二层网络中传播；
（2）因更改配置参数，网络中设备或链路出现故障等原因，引发STP重计算时，有可
能产生TC报文；来源
（3）来自用户设备的攻击TC报文也可能传入其所接入的二层网络；
了解了TC报文的来源，就可以有针对的进行TC的抑止了。主要的措施如下：
（1）连接终端的端口使能了STP，配置边缘端口，同时启用BPDU保护；或者连接终
端的端口上去使能STP；或者根据具体应用情况，在连接终端的端口上配置BPDU Drop；
（2）在开局时就做好网络规划。除非征的局方同意，杜绝在现网更改配置参数；
（3）在我司设备的网络和其他厂商用户设备的网络交界处，只有单条路径连接的，在
该链路所连端口上配置STP Disable或者BPDU Drop；存在多条路径的，对其异常收TC情
况进行监控和检查；
而对于网络中设备或链路出现故障等原因，引发STP重计算，产生的TC报文是正常协
议运行的TC报文，不是故障；
TC报文产生的根源是两个：
（1）设备主动发送2）恶意用户攻击；
设备主动发送TC报文需要满足下面两个条件：
（1）非边缘端口角色从Disable，Alternate，Backupr端口变为Root，Desgin，Master；
（2）端口状态从Discarding变为Forwarding；
设备转发TC报文有两个步骤：
（1）设备从Root，Desgin，Master端口上收到TC报文
（1）向本交换机的所有非边缘的Root，Desgin，Master端口上发送出去；