CCNA640-802 v13题库试题中文分析详解 - 图文

router(config-line)# enable secret cisco router(config-line)# login C. router(config)# line console 0 router(config-line)# password cisco router(config-line)# login D. router(config)# line vty 0

router(config-line)# enable password cisco E. router(config)# line vty 0

router(config-line)# enable secret cisco router(config-line)# login F. router(config)# line vty 0 router(config-line)# password cisco router(config-line)# login

Answer: F

解释一下：telnet是一个应用层的应用，他使用的是vty线路，而且在默认的情况下，是需要访问的线路下设有密码的。而在VTY线路下设置密码的命令为 passwork string ,而VTY线路下的另一个命令login则是默认的，可写也可不写。如果想Telnet时在VTY线路下不设置密码也可以访问这个线路，可以在该VTY线路下输入命令 no login。

34. Refer to the exhibit. The two exhibited devices are the only Cisco devices on the network. The serial network between the two devices has a mask of 255.255.255.252. Given the output that is shown, what three statements are true of these devices? (Choose three.)

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A. The Manchester serial address is 10.1.1.1. B. The Manchester serial address is 10.1.1.2. C. The London router is a Cisco 2610. D. The Manchester router is a Cisco 2610.

E. The CDP information was received on port Serial0/0 of the Manchester router. F. The CDP information was sent by port Serial0/0 of the London router.

Answer: ACE

解释一下：ＣＤＰ是ＣＩＳＣＯ私有的一个二层的协议，但是他却可以发现三层的ＩＰ信息的．通过ＣＤＰ可以发现的邻居的信息有：设备的名称，ＩＰ地址，端口，能力，平台，对端的holddown time．在上图的show cdp entry *命令的显示可以看到的信息有：设备名称：Ｌondon；ＩＰ地址：10.1.1.2；平台：cisco 2610；能力：Router；端口：s0/１；holdtime：１２５Ｓ．Ｍanchesteter收到这个ＣＤＰ信息的接口为S0/0．

综合一下，这个题目的答案就出来了．

35. A network administrator has configured two switches, named London and Madrid, to use VTP. However, the switches are not sharing VTP messages. Given the command output shown in the graphic, why are these switches not sharing VTP messages?

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A. The VTP version is not correctly configured. B. The VTP operating mode is not correctly configured. C. The VTP domain name is not correctly configured. D. VTP pruning mode is disabled. E. VTP V2 mode is disabled. F. VTP traps generation is disabled.

Answer: C

解释一下：交换机间不能共享VTP的信息，我们就需要检查VTP的状态，首先需要检查的是VTP的域名，只有同一个域中的才可能相互学习，再来检查VTP的模式，必须有一个server模式才能有VTP学习的过程的，默认的情况下VTP的模式为Server的。然后我们检查图题目给出的信息，可以看到两台交换机的VTP domain是不一致的，所以这个就是问题的所在了。

36. Host 1 is trying to communicate with Host 2. The e0 interface on Router C is down. Which of the following are true? (Choose two.)

A. Router C will use ICMP to inform Host 1 that Host 2 cannot be reached.

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B. Router C will use ICMP to inform Router B that Host 2 cannot be reached.

C. Router C will use ICMP to inform Host 1, Router A, and Router B that Host 2 cannot be reached. D. Router C will send a Destination Unreachable message type. E. Router C will send a Router Selection message type. F. Router C will send a Source Quench message type.

Answer: AD

解释一下：连Host 2的接口E0/0 down了，那么最直接的反映就发生在路由器C上，C的路由表中的这个条目就消失了，因此当Host 1 想要跟Host 2建立连接的时候，Router C就发送一个目的网段不可达的消息；如果是使用ping命令，那么Router C就使用ICMP 的包文告诉Host 1，Host 2是不可打的。

37. Refer to the exhibit. Assuming that the router is configured with the default settings, what type of router interface is this?

A. Ethernet B. FastEthernet C. Gigabit Ethernet D. asynchronous serial E. synchronous serial

Answer: B

解释一下：这个题是需要根据图中提供的信息来判断接口的类型。可以看到接口的MAC地址，表示这个接口肯定不是串行接口，所以可以排除D和E的选项。看带宽BW 100000 Kbit,表示的是100M的带宽，所以这是个Fast Ethernet接口。

38. On point-to-point networks, OSPF hello packets are addressed to which address? A. 127.0.0.1 B. 172.16.0.1 C. 192.168.0.5 D. 223.0.0.1 E. 224.0.0.5

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