cisco第二学期章节测试3
思科第二学期期末试题及答案

Close WindowAssessment System 1. Assessment Selection 2. Assessment Settings 3. Take Assessment 1Refer to the exhibit. Which summarization should R1 use to advertise its networks to R2? 192.168.1.0/24 192.168.0.0/24 192.168.0.0/22 192.168.1.0/22 2If a router is booting with its default configuration register setting and its NVRAM lacks boot system commands, from try to load the IOS image first? ROM RAM NVRAM f lash flash TFTP server 3Refer to the exhibit. A network administrator adds this command to router R1: ip route 192.168.2.0 255.255.255.0 S0/0/0. result of adding this command? This route is automatically propagated throughout the network. The traffic for network 172.16.1.0 is forwarded to network 192.168.2.0. A static route is established. A static route is established. The traffic for all Class C networks is forwarded to 172.16.1.2. 4Which two technologies can be used in distance vector routing protocols to prevent routing loops? (Choose two.) authentication link-state advertisements h old-down timers hold-down timers Spanning Tree Protocol split horizon 5Refer to the exhibit. What information can be determined from the displayed output? E IGRP packets are waiting to be sent to the neighbors. EIGRP packets are waiting to be sent to the neighbors. The adjacencies between the routers are yet to be established. The IP address 192.168.10.10 is configured at serial interface S0/0/1 of router R2. Router R2 is receiving hello packets from a neighbor with the IP address 192.168.10.10 via the R2 S0/0/1 interf6Which statement is true about the metrics used by routing protocols? A metric is a value used by a particular routing protocol to compare paths to remote networks. A metric is a value used by a particular routing protocol to compare paths to remote networks. A common metric is used by all routing protocols. The metric with the highest value is installed in the routing table. The router may use only one parameter at a time to calculate the metric. 7Which feature of RIPv2 enables it to function as a classless routing protocol? Subnet masks are included in routing updates. Routing updates are triggered by topology changes. Next-hop addresses are included in routing updates. N ext-hop addresses are included in routing updates. Multicast addresses are used to send routing updates. 8Refer to the exhibit. The hosts on the R1 LAN are unable to access the Internet. What is incorrectly configured? the IP address of the Fa0/0 interface at R1 t he IP address of the Fa0/0 interface at R1 the IP address of the S0/0/1 interface at R2 the IP address of the S0/0/0 interface at R1 the subnet mask of the S0/0/1 interface at R2 9Which prompt is used to allow a user to change the IP address of an interface on a router? Router> R outer> Router# Router(config)# Router(config-if)# 10Refer to the exhibit. The interfaces of all routers are configured for OSPF area 0. R3 can ping R1, but the two routeestablish a neighbor adjacency. What should the network administrator do to troubleshoot this problem? Check if the interfaces of the routers are enabled. Check the hello and dead intervals between the routers. C heck the hello and dead intervals between the routers. Check the process ID of both routers. Check if CDP is enabled on all the routers. 11Refer to the exhibit. Which combination of IP address and subnet mask can be used on the serial interface of Route interface in the same network as the serial interface of Router1? IP 172.16.0.18, subnet mask 255.255.255.0 IP 172.16.32.15, subnet mask 255.255.255.240 I P 172.16.32.15, subnet mask 255.255.255.240 IP 172.16.0.18, subnet mask 255.255.255.252 IP 172.16.32.18, subnet mask 255.255.255.252 12Refer to the exhibit. A network engineer has run the show version command on R3. Upon rebooting, R3 does not load configuration settings. What could be the cause of this problem? There is insufficient NVRAM. There is insufficient flash memory. The configuration register is not configured with the default setting. The system image file is not located in NVRAM. 13Refer to the exhibit. On the basis of the show running-config output, which option correctly reflects the routes that will b routing table? 14Refer to the exhibit. Host A is having problems accessing server A. All routers have the same EIGRP configuration a What should be done so that host A can access server A? Add the command n ono auto-summary on all routers. Change the network statements to include a wildcard mask. Adjust the EIGRP hello timers to account for the network delay. Add the command e igrpeigrp log-neighbor-changes on all routers. 15Refer to the exhibit. The network is running the RIP routing protocol. Network 10.0.0.0 goes down. Which statement is the routers in this topology will respond to this event? Router4 will learn about the failed route 30 seconds later in the next periodic update. Split horizon will prevent Router4 from fowarding packets to the 10.0.0.0 network until the holddown timer expire Router5 immediately flushes the unreachable route from its routing table. Router5 will send Router4 a triggered update with a metric of 16 for network 10.0.0.0. 16A network administrator is in charge of two separate networks that share a single building. What device will be require networks and add a common connection to the Internet that can be shared? hub router access point Ethernet switch E thernet switch 17Refer to the exhibit. A network administrator has configured OSPF using the following command: network 192.168.1.32 0.0.0.31 area 0Which router interface will participate in OSPF? FastEthernet0/0 FastEthernet0/1 Serial0/0/0 Serial0/0/1 18Refer to the exhibit. R1 is configured properly for a single area OSPF, and R2 has been recently installed in the netcommands is required to configure a single area OSPF for the networks that are connected to R2? R2(config)# router ospf 1R2(config-router)# network 192.168.2.0 0.0.0.255 area 0R2(config-router)# network 10.1.1.0 0.0.0.3 area 0R2(config)# router ospf 1R2(config-router)# network 192.168.2.0 0.0.0.255 area 0R2(config)# router ospf 2R2(config-router)# network 10.1.1.0 0.0.0.3 area 0R2(config)# router ospf 1R2(config-router)# network 192.168.2.0 0.0.0.255 area 0R2(config-router)# network 10.1.1.0 0.0.0.3 area 1R2(config)# router ospf 1R2(config-router)# network 192.168.2.0 0.0.0.255 area 0R2(config-router)# network 10.0.0.0 0.0.0.3 area 119Which two statements are true for link-state routing protocols? (Choose two.) Routers that run a link-state protocol can establish a complete topology of the network. Routers in a multipoint network that run a link-state protocol can exchange routing tables. Routers use only hop count for routing decisions. The shortest path first algorithm is used. Split horizon is used to avoid routing loops. 20Which candidate route has the longest match for a packet with a destination address of 10.30.16.48? 10.30.0.0/16 10.30.15.0/23 10.30.16.0/24 10.30.16.32/27 10.30.16.32/30 21Which statement is true about the RIPv1 protocol? It is a link-state routing protocol. It excludes subnet information from the routing updates. It uses the DUAL algorithm to insert backup routes into the topology table. It uses classless routing as the default method on the router. 22Which of the following are primary functions of a router? (Choose two.) packet switching microsegmentation domain name resolution path selection flow control 23Refer to the exhibit. Partial results of the show running-config and s how show ip route commands are displayed. Router B rec with a destination address of 10.16.1.97. What will router B do? drop the packet forward the packet via the route to 10.16.1.0 f orward the packet via the route to 10.16.1.64 forward the packet via the route to 10.16.1.64 use the default route 24 What are two ways that a router can learn of the paths to destination networks? (Choose two.) updates from other routers DHCP information broadcasts m anual configuration of routes manual configuration of routes ARP requests from connected routers inspection of the destination IP address in data packets updates from the SMTP management information base 25Refer to the exhibit. Host A is unable to access the Internet. What is the reason for this? The IP address of host A is incorrect. The default gateway of host A is incorrect. The Fa0/1 interfaces of the two routers are configured for different subnets. T he Fa0/1 interfaces of the two routers are configured for different subnets. The subnet mask for the Fa0/0 interface of R1 is incorrect. 26A network administrator is analyzing routing update behavior on a network that has both EIGRP and OSPF configured protocols appear in the output of show ip protocols. However, only EIGRP internal routes appear in the routing tables. correctly explains the scenario? The OSPF protocol has a higher cost than EIGRP. T he OSPF protocol has a higher cost than EIGRPThe EIGRP protocol has a lower metric than OSPF. The EIGRP protocol was configured first on the router. The EIGRP protocol has a lower administrative distance than OSPF. 27Refer to the exhibit. The network has three connected routers: R1, R2, and R3. The routes of all three routers are d are operational and pings are not blocked on this network. Which ping will fail? from R1 to 172.16.1.1 from R1 to 192.168.3.1 from R2 to 192.168.1.1 from R2 to 192.168.3.1 28Refer to the exhibit. A device is required to complete the connection between router R1 and the WAN. Which two de this? (Choose two.) a CSU/DSU device a modem a n Ethernet switch an Ethernet switch a hub a bridge 29 In which situation would a default static route be recommended? when connecting an edge router to the Internet w hen variable length subnet masking is in effect when variable length subnet masking is in effect when there is more than one valid route for a destination network when a destination network has a larger mask than any routes in the routing table 30 Two routers need to be configured within a single OSPF area. Which two components need to be configured on boththis? (Choose two.) t he same process ID the same process ID the same area ID network addresses and wildcard masks the same router ID the same loop back address 231Refer to the exhibit. What is the meaning of the highlighted value 120? It is the metric that is calculated by the routing protocol. It is the value that is used by the DUAL algorithm to determine the bandwidth for the link. It is the administrative distance of the routing protocol. It is the hold-down time, measured in seconds, before the next update. 32Refer to the exhibit. A router learns a route to the 192.168.6.0 network, as shown in the output of the show ip rip database However, upon running the show ip route command, the network administrator sees that the router has installed a diff command, the network administrator sees that the router has installed a diffe 192.168.6.0 network learned via EIGRP. What could be the reason for the missing RIP route? Compared to RIP, EIGRP has a lower administrative distance. Compared to EIGRP , RIP has a higher metric value for the route. Compared to RIP , the EIGRP route has fewer hops. Compared to RIP , EIGRP has a faster update timer. 33 Which mechanism helps to avoid routing loops by advertising a metric of infinity? route poisoning split horizon hold-down timer triggered updates 34 A network administrator must use the subnet 172.16.128.0/18 to create 6 additional subnets each containing up to 20LANs. Which subnet mask should the administrator use to create the new subnets? 255.255.224.0 255.255.240.0 255.255.248.0 255.255.252.0 35 A technician configures the Fa0/0 interface on a router with ip address 192.168.3.5 255.255.255.252. What additional com. What additional com issued by the technician to activate the interface to forward traffic? Router(config-if)# exitRouter(config-if)# no shutdownRouter(config-if)# clock rateRouter# copy running-config startup-config36 Because of a topology change, the next hop IP address in the current static route must be reconfigured. How can a altered to accommodate a topology change? Keep the existing static route and configure a new static route with the correct next hop IP address. Negate the existing static route and configure a new static route with the correct next hop IP address. D o nothing. The existing static route will automatically update the next hop entry with the new IP address. Do nothing. The existing static route will automatically update the next hop entry with the new IP address. Keep the existing static route, reload the router, and configure a new static route with the correct next hop IP a37Refer to the exhibit. What needs to be done to allow these two routers to connect successfully? Add a clock rate to S0/0/0 on R1. Add an interface description to S0/0/1 on R2. C hange the serial interface on R2 to S0/0/0 so that it matches R1. Change the serial interface on R2 to S0/0/0 so that it matches R1. Change the IP address of S0/0/1 on R2 so that it is in the same subnet as R1. 38Refer to the exhibit. The network administrator has run the following command on R1. R1(config)# ip route 192.168.2.0 255.255.255.0 172.16.1.2What is the result of running this command? Traffic for network 192.168.2.0 is forwarded to 172.16.1.2. This route is automatically propagated throughout the entire network. Traffic for all networks is forwarded to 172.16.1.2. The command invokes a dynamic routing protocol for 192.168.2.0. 39 Why is fast convergence desirable in networks that use dynamic routing protocols? Hosts are unable to access their gateway until the network is converged. Routers will not allow packets to be forwarded until the network is converged. Routers may make incorrect forwarding decisions until the network has converged. Routers will not allow configuration changes to be made until the network has converged. 40Refer to the exhibit. When all of the commands that are shown in the exhibit are entered at the correct router promp the router? name cisco router hostname 41Refer to the exhibit. Packets destined to which two networks will require the router to perform a recursive lookup? (C10.0.0.0/8 64.100.0.0/16 128.107.0.0/16 172.16.40.0/24 192.168.1.0/24 192.168.2.0/24 42Refer to the exhibit. A router interface is configured with the command ip address 172.16.3.31 255.255.192.0. Which set o. Which set o values would allow a computer that is connected to the router interface to communicate with remote networks? A: 172.16.3.254 A: 172.16.3.254 B: 255.255.192.0 C: 172.16.3.31 A: 172.16.3.31 B: 255.255.192.0 C: 172.16.3.255 A: 172.16.3.254 B: 255.255.255.0 C: 172.16.3.31 A: 172.16.3.31 B: 255.255.255.0 C: 172.16.3.1 43Which three statements are true regarding the encapsulation and de-encapsulation of packets when traveling through three.) The router modifies the TTL field, decrementing it by one. The router changes the source IP to the IP of the exit interface. The router maintains the same source and destination IP. The router changes the source physical address to the physical address of the exit interface. The router changes the destination IP to the IP of the exit interface. The router sends the packet out all other interfaces, besides the one it entered the router on. 44Refer to the exhibit. Which three statements are true of the routing table for Router1? (Choose three.) The route to network 172.16.0.0 has an AD of 156160. Network 192.168.0.16 can best be reached using FastEthernet0/0. The AD of EIGRP routes has been manually changed to a value other than the default value. Router1 is running both the EIGRP and OSPF routing process. Network 172.17.0.0 can only be reached using a default route. No default route has been configured. N o default route has been configured. 45Refer to the exhibit. Which route will be installed in the routing table on R1 to forward traffic from PC1 to the web s the static route the route learned via OSPF the route learned via EIGRP both routes learned via OSPF and EIGRP 46Refer to the exhibit. Based on the partial output in the exhibit, why can users establish a console connection to this r a password? The login command was not entered on the console line. The enable password should be an enable secret password. No username and password combination has been configured. Console connections cannot be configured to require users to provide passwords. 47Refer to the exhibit. Which path will traffic from the 172.16.1.0/24 network take to get to the 10.0.0.0/24 network? ADC ABC It will load balance the traffic between ADC and ABC It will send the traffic via ABC, and will use ADC as a backup path only when ABC fails. 48A router learns about network 192.168.10.128/27 from multiple sources. Which option represents the best route and w routing table? S 192.168.10.128/27 [1/0] via 192.168.10.226 R 192.168.10.128/27 [120/2] via 192.168.10.226, 00:00:14, Serial0/0/0 O 192.168.10.128/27 [110/1563] via 192.168.10.226, 00:00:09, Serial0/0/0 D 192.168.10.128/27 [90/21026560] via 192.168.10.226, 00:00:16, Serial0/0/0 49Refer to the exhibit. R1 and R2 are adjacent routers both running RIP. All interfaces on both routers are correctly cothe routing table. What is the likely cause? The adjacent interfaces are passive. The distance of 120 exceeds 15 hops. R2 will not accept version 1 updates from R1. Routes are being summarized by R1 but not by R2. 50It is saved in the topology table for use if the primary route fails. It may be backed up by a feasible successor route. It is used by EIGRP to forward traffic to the destination. It is flagged as active in the routing table. After the discovery process has occurred, the successor route is stored in the neighbor table. 51Refer to the exhibit. PC1 is unable to access the Internet. What is the cause of the problem? An incorrect IP address is configured between the two routers. No static route is configured on Router2. A routing loop has occurred. No routing protocol is configured on either of the two routers. 52Refer to the exhibit. A technician has configured the interfaces on the Router, but upon inspection discovers that inte FastEthernet0/1 is not functioning. Which action will most likely correct the problem with FastEthernet0/1? A clock rate should be added to the interface configuration. The subnet mask should be added to the interface configuration. An interface description needs to be added to the interface configuration. The no shutdown command needs to be added to the interface configuration. 。
ccna第二学期练习答案

ERouting Chapter 1 - CCNA Exploration: 路由协议和概念 (版本1口令可用于限制对 Cisco IOS 所有或部分内容的访问。
请选择可以用口令保护的模式和接口。
(选择三项。
)VTY 接口控制台接口特权执行模式2路由器从相连的以太网接口收到消息后,会更改哪项报头地址,再将消息从另一个接口发送出去第 2 层源地址和目的地址3请参见图示。
网络管理员已经为路由器连接到直连网络的接口配置了如图所示的 IP 地址。
从路由器 ping 相连网络上的主机口之间相互 ping 都会遭到失败。
此问题最可能的原因是什么必须使用no shutdown命令启用接口。
4请参见图示。
主机 A ping 主机 B。
当 R4 收到对以太网接口的 ping 时,哪两块报头信息包括在内(选择两项。
)目的 IP 地址:目的 MAC 地址:5网络管理员刚把新配置输入 Router1。
要将配置更改保存到 NVRAM,应该执行哪一条命令Router1# copy running-config startup-config6您需要配置图中所示的串行连接,必须在 Sydney 路由器上发出以下哪条配置命令才能与 Melbourne 站点建立连接(选择三Sydney(config-if)# ip addressSydney no shutdownSydney(config-if)# clock rate 560007请参见图示。
从路由器的运行配置输出可得出什么结论显示的命令决定了路由器的当前运行情况。
8请参见图示。
在主机 2 连接到 LAN 上的交换机后,主机 2 无法与主机 1 通信。
导致此问题的原因是什么主机 1 和主机 2 位于不同的网络中。
9输入以下命令的作用是什么R1(config)# line vty 0 4R1(config-line)# password check123R1(config-line)# login设置通过 Telnet 连接该路由器时使用的口令10以下哪一项正确描述了路由器启动时的顺序加载 bootstrap、加载 IOS、应用配置11加载配置文件时的默认顺序是怎样的NVRAM、TFTP、CONSOLE12请参见图示。
ccna第二学期练习题中文答案..

ERouting Chapter 1 - CCNA Exploration: 路由协议和概念(版本4.0)1口令可用于限制对Cisco IOS 所有或部分内容的访问。
请选择可以用口令保护的模式和接口。
(选择三项)VTY 接口控制台接口以太网接口加密执行模式特权执行模式路由器配置模式2路由器从相连的以太网接口收到消息后,会更改哪项报头地址,再将消息从另一个接口发送出去?仅第 2 层源地址仅第 2 层目的地址仅第 3 层源地址仅第 3 层目的地址第 2 层源地址和目的地址第 3 层源地址和目的地址3请参见图示。
网络管理员已经为路由器连接到直连网络的接口配置了如图所示的IP 地址。
从路由器ping 相连网络上的主机之间相互ping 都会遭到失败。
此问题最可能的原因是什么?目的网络不存在。
路由器接口的IP 地址必须配置为网络地址而非主机地址。
必须使用no shutdown命令启用接口。
每个接口都必须使用clock rate命令配置4请参见图示。
主机 A ping 主机B。
当R4 收到对以太网接口的ping 时,哪两块报头信息包括在内?(选择两项。
)源IP 地址:192.168.10.129源IP 地址:BBBB.3333.5677源MAC 地址:5555.AAAA.6666目的IP 地址:192.168.10.33目的IP 地址:192.168.10.134目的MAC 地址:9999.DADC.12345网络管理员刚把新配置输入Router1。
要将配置更改保存到NVRAM,应该执行哪一条命令?Router1# copy running-config flashRouter1(config)# copy running-config flashRouter1# copy running-config startup-configRouter1(config)# copy running-config startup-configRouter1# copy startup-config running-configRouter1(config)# copy startup-config running-config6您需要配置图中所示的串行连接,必须在Sydney 路由器上发出以下哪条配置命令才能与Melbourne 站点建立连接?(选Sydney(config-if)# ip address 201.100.53.2 255.255.255.0Sydney(config-if)# no shutdownSydney(config-if)# ip address 201.100.53.1 255.255.255.224Sydney(config-if)# clock rate 56000Sydney(config-if)# ip host Melbourne 201.100.53.27请参见图示。
思科考试真题和答案

思科考试真题和答案****一、单选题1. 以下哪项是思科设备默认的VLAN?A. VLAN 1B. VLAN 10C. VLAN 100D. VLAN 200答案:A2. 思科设备默认的管理VLAN是哪个?A. VLAN 1B. VLAN 10C. VLAN 20D. VLAN 100答案:A3. 在思科设备上,以下哪个命令可以查看当前设备的VLAN信息?A. show vlanB. show interfaceC. show running-configD. show ip interface brief答案:A4. 在思科设备上,以下哪个命令可以进入全局配置模式?A. enableB. configure terminalC. privileged execD. user exec答案:B5. 在思科设备上,以下哪个命令可以查看设备的接口状态?A. show interfaceB. show running-configC. show vlanD. show ip interface brief答案:A二、多选题1. 以下哪些命令可以在思科设备上创建VLAN?A. vlan <vlan_id>B. configure terminalC. interface vlan <vlan_id>D. switchport mode access答案:A, C2. 在思科设备上,以下哪些命令可以配置接口为Trunk模式?A. switchport mode trunkB. switchport trunk encapsulation dot1qC. switchport nonegotiateD. switchport mode dynamic auto答案:A, B, C, D3. 以下哪些命令可以在思科设备上查看接口的Trunk信息?A. show interfaces trunkB. show interface statusC. show vlanD. show running-config答案:A, B三、判断题1. 思科设备默认的VLAN是VLAN 1。
CCNA 思科网络章节考试题及答案《网络规划和布线》

《网络规划和布线》在IPv4 环境中,路由器根据什么信息在不同的路由器接口之间转发数据包?目的网络地址源网络地址源MAC 地址公认端口目的地址OSI 第3 层封装期间添加什么信息?源MAC 地址和目的MAC 地址源应用程序协议和目的应用程序协议源端口号和目的端口号源IP 地址和目的IP 地址在无连接系统中,下列哪项陈述是正确的?发送数据包之前联系目的设备。
发送数据包之前不联系目的设备。
目的设备向源设备发送确认,表示已经收到数据包。
目的设备向源设备发送确认,请求发送下一个数据包。
IP 数据包的哪个字段用于防止无限循环?服务类型标识标志生存时间报头校验和路由器使用网络层地址的哪个部分转发数据包?主机部分广播地址网络部分网关地址请参见图示。
如果使用图示中的网络,下列哪一项将成为192.133.219.0 网络中主机A 的默认网关地址?192.135.250.1192.31.7.1192.133.219.0192.133.219.1如果主机上的默认网关配置不正确,对通信有何影响?该主机无法在本地网络上通信。
该主机可以与本地网络中的其它主机通信,但不能与远程网络上的主机通信。
该主机可以与远程网络中的其它主机通信,但不能与本地网络中的主机通信。
对通信没有影响。
默认网关有何作用?用于物理连接计算机和网络为计算机提供永久地址标识计算机所连接的网络标识网络计算机的逻辑地址,并且是网络中的唯一标识允许本地网络计算机和其它网络中的设备通信的设备标识哪种路由使用的信息需要手动输入路由表中?动态内部静态标准如果目的网络未列在Cisco 路由器的路由表中,路由器可能会采取哪两项措施?(选择两项)路由器发送ARP 请求以确定所需的下一跳地址。
路由器丢弃数据包。
路由器将数据包转发到ARP 表所示的下一跳。
路由器将数据包转发到源地址所示的接口。
路由器将数据包从默认路由条目所确定的接口发出。
将主机分组到同一个网络时应考虑哪些关键因素?(选择三项)网关用途物理编址软件版本地理位置所有权以下哪一项是路由表条目的组成部分?路由器接口的MAC 地址第 4 层目的端口号目的主机地址下一跳地址下列哪些中间设备可用于在网络之间实施安全保护?(选择两项)路由器集线器交换机防火墙接入点网桥大型网络存在哪三个常见问题?(选择三项)广播太少性能下降安全问题管理职责受限制主机标识协议兼容性请参见图示。
CISCO第二学期期末考试答案

C I S C O第二学期期末考试答案IMB standardization office【IMB 5AB- IMBK 08- IMB 2C】端口过滤和访问列表通过什么方式来增强网络安全防止特定类型的通信到达特定网络主机。
/遭受各类拒绝服务攻击时提醒网络管理员。
防止病毒、蠕虫和特洛伊木马感染主机计算机和服务器。
可对机密数据通信进行加密和身份认证。
某黑客尝试获取存储在公司网络内部某台服务器上的机密信息。
网络安全解决方案检测完整的数据包,确定这是一个威胁,所以阻止该数据包进入内部网络。
这一过程中哪项安全措施保护了网络 IDS IPS /基于主机的防火墙Anti-X 软件在图中所示的其中一台路由器上执行 show ip route 命令,显示下列输出:1此命令是从哪一台路由器执行的 A B C /D请参见图示。
网络管理员使用以下命令在 RTB 上配置了一条默认路由:RTB(config)# ip route 0.0.010.1.1哪种路由协议可实现不同自治系统之间的路由信息交换 OSPF EIGRP RIP BGP /下列关于 FTP 协议被动数据连接的说法中哪一项正确服务器发起数据传输连接。
服务器将其 IP 地址和一个随机端口号通过控制流转发给 FTP 客户端。
/防火墙不会允许与网络内的主机进行被动数据连接。
客户端将数据转发至服务器的端口 21。
下列关于反向查找 DNS 区域的说法中哪一项正确常用于用户浏览 Internet 时。
是正向查找区域的备份。
动态更新资源记录。
将 IP 地址解析为完全限定的域名。
/下列关于 DNS 层级的说法中哪两项正确(选择两项。
)根服务器维护 Internet 上所有服务器的记录。
DNS 依靠分布于不同层级的服务器维护记录。
/所有 DNS 服务器均负责管理整个 DNS 结构的“域名-IP”映射。
域名解析过程从位于 DNS 顶层的服务器开始。
根服务器负责维护有关如何到达顶层域名服务器的记录。
CCNA第二学期

CCNA 2 - Module 1If a router cannot find a valid configuration file during the startup sequence, what will occur?The router will prompt the user for a response to enter setup mode.Refer to the exhibit. The network administrator has configured the router with the interface IP addresses shown for the directly connected networks. Pings from the router to hosts on the connected networks or pings between router interfaces are not working. What is the most likely problem?The interfaces must be enabled with the no shutdown command.Refer to the exhibit. What can be concluded from the routing table output in the exhibit? (Choose two.) The FastEthernet0/0 and Serial0/0/0 interfaces of this router were configured with an IP address and the no shutdown command.An IP packet received by this router with a destination address of 198.18.9.1 will be forwarded out of the Serial0/0/0 interface.Refer to the exhibit. The frame shown in the exhibit was received by the router. The router interfaces are operational. How will the router process this frame? (Choose two.)The router will change the frame type to one supported by the WAN link before forwarding the frame.The frame was received on the Fa0/0 interface of the router and will be s witched to the S0/0/0 interface.Passwords can be used to restrict access to all or parts of the Cisco IOS. Select the modes and interfaces that can be protected with passwords. (Choose three.)VTY interfaceconsole interfaceprivileged EX EC modeWhich two statements correctly describe the components of a router? (Choose two.)ROM contains diagnostics executed on hardware modules.Flash memory does not lose its contents during a reboot.Refer to the exhibit. After host 2 is connected to the switch on the LAN, host 2 is unable to communicate with host 1. What is the cause of this problem?The subnet mask of host 2 is incorrect.Host 1 and host 2 are on different networks.The switch needs an IP address that is not configured.The router LA N interface and host 1 are on different networks.The IP address of host 1 is on a different network than is the LAN interface of the router.Which are functions of a router? (Choose three.)packet s witchingsegmentation of broadcast domainsselection of best path based on logical addressingRefer to the exhibit. A ll routers have a route in its routing table to each network that is shown in the exhibit. Default routes have not been issued on these routers. What can be concluded about how packets are forwarded in this network? (Choose two.)If RouterA receives a packet that is destined for 192.168.3.146, it will be forwarded out interface S0/0/1.If RouterB receives a packet that is destined for 10.5.27.15, it will be forwarded out interface S0/0/1.The serial connection shown in the graphic needs to be configured. Which configuration commands must be made on the Sydney router to establish connectivity with the Melbourne site? (Choose three.) Sydney(config-if)# ip address 201.100.53.2 255.255.255.0Sydney(config-if)# no shutdownSydney(config-if)# clock rate 56000Refer to the exhibit. What can be concluded from the output of the running-configuration of a router? The commands that are dis played determine the current operation of the router.Refer to the exhibit. Host A pings host B. When R4 accepts the ping into the Ethernet interface, what two pieces of header information are included? (Choose two.)destination IP address: 192.168.10.134destination MAC address: 9999.DADC.1234What is the outcome of entering these commands?R1(config)# line vty 0 4R1(config-line)# password check123R1(config-line)# loginsets the password to be used for connecting to this router via T elnetWhich of the following is the correct flow of routines for a router startup?load bootstrap, load IOS, apply configurationWhat three processes does a router execute when it receives a packet from one network that is destinedfor another network? (Choose three.)decapsulates the Layer 3 packet by stripping off the Layer 2 frame headeruses the destination IP Address in the IP header to look up the next-hop address in the routing tableencapsulates the Layer 3 packet into the new Layer 2 frame and forwards it out the exit interfaceThe network administrator needs to connect two routers directly via their FastEthernet ports. What cable should the network administrator use?cross-overWhich two statements describe characteristics of load balancing? (Choose two.)Load balancing allows a router to forward packets over multiple paths to the same destination network.Unequal cost load balancing is supported by EIGRP.What information about the router and its startup process can be gathered from the output of the show version command? (Choose three.)the last restart methodthe configuration register settingsthe location from where the IOS loadedWhich interfaces in the exhibit could be used for a leased line WAN connection? (Choose two.)14From what location can a router load the Cisco IOS during the boot process? (Choose two.)TFTP serverFlash memoryA network administrator has just entered new configurations into Router1. Which command should be executed to save configuration changes to NVRAM?Router1# copy running-config startup-configWhat is the default sequence for loading the configuration file?NVRAM, TFTP, CONSOLEWhat header address information does a router change in the information it receives from an attached Ethernet interface before information is transmitted out another interface?the Layer 2 source and destination addressCCNA 2 - Module 2Which of the following are displayed by the Router# show cdp neighbors command? (Choose three.)platformholdtimelocal interfaceWhy is it advisable to enter a next-hop IP address when creating a static route whose exit interface is an Ethernet network?In a multi-access network, the router cannot determine the next-hop MAC address for the Ethernet frame without a next-hop address.The output of the Router# show interfaces serial 0/1 command displays the following: Serial0/1 is up, line protocol is down.What is the most likely cause for the line protocol being down?No clock rate has been set.A static route that points to the next hop IP will have what administrative distance and metric in the routing table?administrative distance of 1 and metric of 0Refer to the exhibit. What two commands will change the next-hop address for the 10.0.0.0/8 network from 172.16.40.2 to 192.168.1.2? (Choose two.)A(config)# no ip route 10.0.0.0 255.0.0.0 172.16.40.2A(config)# ip route 10.0.0.0 255.0.0.0 192.168.1.2Refer to the exhibit. A company network engineer is assigned to establish connectivity between the two Ethernet networks so that hosts on the 10.1.1.0/24 subnet can contact hosts on the 10.1.2.0/24 subnet. The engineer has been told to use only static routing for these company routers. Which set of commands will establish connectivity between the two Ethernet networks?R1(config)# ip route 10.1.1.0 255.255.255.0 192.168.0.2R2(config)# ip route 10.1.2.0 255.255.255.0 192.168.0.1Refer to the exhibit. Which static route should be configured on Router1 so that hostA will be able to reach hostB on the 172.16.0.0 network?ip route 172.16.0.0 255.255.0.0 S0/0/0Which address can be used to summarize networks 172.16.0.0/24 thru 172.16.7.0/24?172.16.0.0/21Refer to the exhibit. What is the significance of the /8 in the route to the 10.0.0.0 network?It indicates the number of consecutive bits, from the left, in the destination IP address of a packet that must match 10.0.0.0 to use that route.What two devices are responsible for converting the data from the WAN service provider into a form acceptable by the router? (Choose two).a modema CSU/DSU deviceA network administrator enters the following command into Router1: ip route 192.168.0.0 255.255.255.0 S0/1/0. Router1 then receives a packet that is destined for192.168.0.22/24. After finding the recently configured static route in the routing table, what does Router1 do next to process the packet?encapsulates the packet into a frame for the WAN link and forwards the packet out the S0/1/0 interfaceWhich piece of information is available from examining the output of the command show ip interface brief?Interface IP addressWhich of the following is true regarding CDP and the graphic shown?By default, Router A will receive CDP advertisements from routers B and C.Which two statements describe functions or characteristics of CDP? (Choose two.)It starts up automatically and allows the device to detect directly connected neighbor devices that use CDP.It allows systems to learn about each other even if different network layer protocols are configured.Hosts on two separate subnets cannot communicate. The network administrator suspectsa missing route in one of the routing tables. Which three commands can be used to help troubleshoot Layer 3 connectivity issues? (Choose three.)pingtracerouteshow ip routeWhat happens to a static route entry in a routing table when the outgoing interface is not available?The route is removed from the table.The routers in the diagram use the subnet assignments shown. What is the most efficient route summary that can be configured on Router3 to advertise the internal networks to the cloud?192.1.1.0/25Refer to the exhibit. How will packets destined to the 172.16.0.0 network be forwarded? Router1 will perform recursive lookup and packet will exit S0/0.A router has one static route configured to each destination network. Which two scenarios would require an administrator to alter the static routes that are configured on that router? (Choose two.)The destination network no longer exists.A topology change occurs where the existing next-hop address or exit interface is not accessible.Refer to the exhibit. Given the output in the exhibit, how would a clock rate be determined for this link?The rate configured on the DCE determines the clock rate.Refer to the exhibit. Which set of commands will configure static routes that will allow the WinterPark and the Altamonte routers to deliver packets from each LAN and direct all other traffic to the Internet?WinterPark(config)# ip route 0.0.0.0 0.0.0.0 192.168.146.1Altamonte(config)# ip route 10.0.234.0 255.255.255.0 192.168.146.2Altamonte(config)# ip route 0.0.0.0 0.0.0.0 s0/1Refer to the exhibit. What two commands are required to provide connectivity betw een the 192.168.1.0 and 10.0.0.0 networks without requiring recursive lookup? (Choose two.)A(config)# ip route 10.0.0.0 255.0.0.0 s 0/1/0B(config)# ip route 192.168.1.0 255.255.255.0 s 0/0/0CCNA 2 - Module 3Which two statements correctly describe the concepts of administrative distance and metric? (Choose two.)Administrative distance refers to the trustworthiness of a particular route.Routes with the smallest metric to a destination indicate the best path.Refer to the exhibit. Which statement correctly describes how R1 will determine the best path to R2?R1 will install an EIGRP route using network B in its routing table because the administrative distance of EIGRP is lower than RIP.Which two statements are true regarding classless routing protoc ols? (Choose two.) sends subnet mask information in routing updatesallows for use of both 192.168.1.0/30 and 192.168.1.16/28 subnets in the same topologyWhich command would the network administrator issue to determine if load balancing is in effect on a router?show ip routeWhich statement is true regarding routing protocols?EIGRP uses DUAL to calculate the shortest path and can be configured to do unequal cost load balancing.Which two conditions would create a setting where the use of a distance-vector routing protocol would be efficient? (Choose two.)the network is using a hub and spoke topologythe network is using a flat designWhat is the purpose of a routing protocol?It allows a router to share information about known networks with other rou ters.Which of the following best describes the operation of distance vector routing protocols? They send their routing tables to directly connected neighbors.Which of the following is associated with link-state routing protocols?shortest-path first calculationsWhy is fast convergence desirable in networks that use dynamic routing protocols? Routers may make incorrect forwarding decisions until the network has converged.Which of the following conditions must be met in order for a network to have con verged The routers in the network are operating with consistent routing knowledge.Which two statements are true regarding metrics? (Choose two.)EIGRP uses bandwidth as a metric.OSPF uses cost based on bandwidth as a metric.Which two statements are true regarding the advantages of the use of static routes? (Choose two).increased securitythe administrator maintains control over routingThe following line of code is displayed in a routing table:R 209.165.201.0/24 [120/2] via 192.168.252.2, 00:00:16, S0/0/0What can be concluded from this output?The value, 120, is used to determine the best path when a router has more than one routing protocol configured for the same destination network.What will be the result of the following commands?ORL(config)# interface fastethernet 0/0ORL(config-if)# ip address 172.16.3.1 255.255.255.0ORL(config-if)# no shutdownA routing table entry is made to the 172.16.3.0 network with a code of "C".An engineer creates a static route by entering the Router(config)# ip route 10.0.0.0 255.255.255.0 192.168.1.2 command. What can be concluded about this route?The administrative distance of this route is 1.Refer to the exhibit. Router1 and Router2 are running EIGRP. All interfaces are operational and packets can be forwarded between all networks. What information will be found in the routing table for Router1?The administrative distance of the route to network 172.16.0.0 will be 90.The following line of code is present in the routing table:O 10.16.1.0/27 [110/129] via 192.168.1.5, 00:00:05, Serial0/0/1What does the number 129 indicate in this output?The cost for this link has a value of 129.A growing medium-sized manufacturing company recently began to have routing instability issues. The company uses static routes and has a mixture of over 30 Cisco and non-Cisco routers. The network administrator has decided to convert the network to dynamic routing. What characteristics of protocols should be considered in this selection process?OSPF can be used between the routers.Refer to the exhibit. If RIP is the routing protocol, what is the value of the metric from router A to network 192.168.5.0/24?3A router learns two paths with equal metrics to a destination network via the RIP routing protocol. How will the router handle packets to the destination network?The router will install both routes in the routing table and load balance between the two.CCNA 2 - Module 4Which event will cause a triggered update?a route is installed in the routing tableThree routers running a distance-vector routing protocol lost all power, including the battery backups. When the routers reload, what will happen?They will send updates that include only directly connected routes to their directly connected neighbors.What does the RIP holddown timer do?instructs routers to ignore updates, for a specified time or event, about possible inaccessible routesWhich two statements are true regarding the function of the RIPv1 routing updates? (Choose two).updates are broadcast at regular intervalsbroadcasts are sent to 255.255.255.255Which of the following statements are correct about RIP?will send out an update if there is a failure of a linkWhich two statements describe EIGRP? (Choose two.)EIGRP sends triggered updates whenever there is a change in topology that influences the routing information.EIGRP sends a partial routing table update, which includes just routes that have been changed.Which statement is true regarding cisco’s RIP_JITTER variable?It prevents the synchronization of routing updates by subtracting a random length of time ranging from 0% to 15% of the specified interval time from the next routing update interval.What actions will occur after RouterA loses connectivity to network 114.125.16.0? (Choose two.)RouterB will include network 123.92.76.0 and 136.125.85.0 in its update to RouterA.Router C will learn of the loss of connectivity to network 114.125.16.0 from RouterB.Which of the following methods does split horizon use to reduce incorrect routing information?Information learned from one source is not distributed back to that source.The graphic shows a network that is configured to use RIP routing protocol. Router2 detects that the link to Router1 has gone down. It then advertises the network for this link with a hop count metric of 16. Which routing loop prevention mechanism is in effect?route poisoningWhat is the purpose of the TTL field in the IP header?limits the time or hops that a packet can traverse through the network before it should be discardedWhich of the following can exist in a distance vector network that has not converged? (Choose three.)routing loopsinconsistent traffic forwardinginconsistent routing table entriesRefer to the exhibit. The routers in this network are running RIP. Router A has not received an update from Router B in over three minutes. How will Router A respond?The Invalid timer will mark the route as unusable if an update has not been received in 180 seconds.A network administrator is evaluating RIP versus EIGRP for a new network. The network will be sensitive to congestion and must respond quickly to topology changes. What are two good reasons to choose EIGRP instead of RIP in this case? (Choose two.)EIGRP only updates affected neighbors.EIGRP updates are partial.Refer to the exhibit. What path will packets from the 192.168.1.0/24 network travel to reach the 10.0.0.0/8 network if RIP is the active routing protocol?The path will be router A -> router D -> router E.Which three routing protocols are distance vector routing proto cols? (Choose three).RIPv1EIGRPRIPv2What is a routing loop?a condition where a packet is constantly transmitted within a series of routers without ever reaching its intended destinationWhich two conditions are most likely to cause a routing loop? (Choose two.)inconsistent routing tablesincorrectly configured static routesWhat metric does the RIP routing protocol consider to be infinity?16What does a router running RIP do first with a new route that is received from an advertisement?adjusts the metric for the new route to show the added distance for the routeRefer to the exhibit. If all routers are using RIP, how many rounds of updates will occur before all routers know all networks?3CCNA 2 - Module 5Refer to the exhibit. The network that is shown is running RIPv1. The 192.168.10.0/24 network was recently added and will only contain end users. What command or set of commands should be entered on Router1 to prevent RIPv1 updates from being sent to the end user devices on the new network while still allowing this new network to be advertised to other routers?Router1(config-router)# passive-interface fastethernet 0/0The following line was displayed in the output of the show ip route command.R 192.168.3.0/24 [120/3] via 192.168.2.2, 00:00:30, Serial0/0What is the value of the routing metric?3Which of the following is considered a limitation of RIP v1?RIP v1 does not send subnet mask information in its updates.Refer to the exhibit. The Ethernet interface on Router2 goes down and the administrator notices that the route is still in the Router1 routing table. How much longer will Router1 keep the down network in its routing table before marking it as possibly down?155 secondsRefer to the exhibit. Router1 is running RIPv1. What command was entered into Router1 to configure the gateway of last resort?ip route 0.0.0.0 0.0.0.0 S0/0/1What are three characteristics of the RIPv1 routing protocol? (Choose three.)uses hop count as a metricconsiders a metric of 16 as infinitycalculates metrics using the Bellman Ford algorithmWhich of the following would be the correct command sequence to enable RIP on Router B for all connected networks?RouterB(config)# router ripRouterB(config-router)# network 198.16.4.0RouterB(config-router)# network 210.36.7.0RouterB(config-router)# network 220.17.29.0What is the default update period in seconds for the RIP routing protocol?30Refer to the exhibit. What can be concluded from the routing table output of router B? The default-information originate command has been entered on A.Refer to the exhibit. A network consists of multiple routers. What can be verified when the show ip protocols command is issued on one of the routers in the network? routing protocol configuration in use for IP on this routerRefer to the exhibit. All routers are configured with valid interface addresses in the indicated networks and are running RIPv1. The network is converged. Which routes are present in the routing tables?All routers have all /30 routes. Routers A and E also have some of the /24 routes in their routing table.Which two statements are true regarding the characteristics of RIPv1? (Choose two). It is a distance vector routing protocol.The data portion of a RIP message is encapsulated into a UDP segment.Which command or set of commands will stop the RIP routing process?RouterB(config)# no router ripRefer to the exhibit. All routers in the exhibit are running RIP v1. The network administrator issues the show ip route command on router A. What routes would ap pear in the routing table output if the network is converged? (Choose two).R 192.168.2.0/24 [120/1]R 10.10.1.0/24 [120/2]Which command will display RIP activity as it occurs on a router?debug ip ripRefer to the output from the show ip route command. What can be concluded from the output of this router command?There are two equal cost paths to network 1.0.0.0.Refer to the exhibit. Router1 and Router2 are running the RIPv1 protocol. The network administrator configures the command network 10.1.0.0 on Router1. What network will Router1 advertise to Router2?10.0.0.0/8Refer to the exhibit. Pings between the serial interfaces of the routers are successful. Hosts on each LAN can ping the Fa0/0 interface of the router to which they are directlyconnected through the switch. However, pings between hosts on the 10.1.1.0/24 and 10.1.2.0/24 networks are unsuccessful. What is a likely cause of this problem?RIP is configured incorrectly on R1.What will happen if an interface IP address is entered for the address portion of the network command in a RIPv1 configuration instead of a network address?All interfaces in the same classful network as the configured address will be included in the RIPv1 routing process.Refer to the exhibit. All routers that are shown are running the RIP routing protocol. All unknown IP traffic must be forwarded to the ISP. What router or set of routers are recommended to have both a default route and the default-information originate command issued to implement this forwarding policy?only the gateway routerCCNA 2 - Module 6What two advantages does CIDR provide to a network? (Choose two.)reduced routing table sizereduced routing update trafficRefer to the exhibit. The network administrator wants to create a subnet for the po int-to-point connection between the two routers. Which subnetwork mask would provide enough addresses for the point-to-point link with the least number of wasted addresses?255.255.255.252Refer to the exhibit. A network engineer is summarizing the two groups of routes on router R1 shown in the exhibit. Which summarization will work for all the subnets?192.168.0.0/21Which of the following are contained in the routing updates of classless routing protocols? (Choose two.)32-bit addresssubnet maskWhich of the following problems does VLSM help to alleviate?the shortage of IP addressesWhat does VLSM allow a network administrator to do?utilize multiple subnet masks in the same IP address spaceRefer to the exhibit. What subnet mask will be applied if Router A sends a RIPv1 update for the network 172.16.1.0 to Router B?24Refer to the exhibit. The network administrator wants to minimize the number of entries in Router1’s routing table. What should the administrator implement on the network?CIDRA router has a summary route to network 192.168.32.0/20 installed in its routing table. What range of networks are summarized by this route?192.168.32.0 – 192.168.47.0/24A network administrator is tasked with dividing up a class C network among the QA, Sales, and Administration departments. The QA department is made up of 10 people, the Sales is made up of 28 people, and the Administration has 6. Which two subnets masks adequately address the QA and Sales departments? (Choose two.)255.255.255.224 for Sales255.255.255.240 for QAIn the network shown in the graphic, three bits were borrowed from the host portion of a Class C address. How many valid host addresses will be unused on the three point-to-point links combined if VLSM is not used?84A Class C address has been assigned for use in the network shown in the graphic. Using VLSM, which bit mask should be used to provide for the number of host addresses required on Router A, while wasting the fewest addresses?/27An additional subnet is required for a new Ethernet link between Router1 and Router2 as shown in the diagram. Which of the following subnet addresses can be configured in this network to provide a maximum of 14 useable addresses for this link while wasting the fewest addresses?192.1.1.224/28Which three interior routing protocols support VLSM? (Choose three.)OSPFRIP v2EIGRPRefer to the exhibit. The number of required host addresses for each subnet in a network is listed in the exhibit. This number includes the host address requirements for all router ports and hosts on that subnet. After all device and router port address assignments are determined, what will be the total number of unused host addresses available?29Refer to the exhibit. In the network that is shown, the router interfaces are assigned the first address ineach subnet. Which IP address would be usable for a host on one of the LANs in this network?192.168.2.130/25Refer to the exhibit. Which address is a broadcast address for one of the subnets that are shown in the exhibit?192.168.4.15/29Refer to the exhibit. A network administrator needs to create two subnetworks from 10.0.0.0/8 for a router running RIPv2. The Admin subnet requires 120 hosts and the Sales subnet requires 58 hosts. The network administrator assigned 10.0.1.128/25 to the Admin subnet. The Sales subnet i s given 10.0.1.192/26. What will be the result of this addressing scheme?Because RIPv2 does not support VLSM, the subnet masks will not be allowed.The subnets overlap and will be rejected by the router.Refer to the exhibit. A network technician enters the static route in R1 needed to reach network 10.1.1.0/24. A ping from the S0/0/0 interface on R1 to host B fails. The technician begins testing the network and has the following results:1. pings from R1 to the S0/0/0 interface on R2....successful2. pings from R1 to the Fa0/0 interface on R2....successful3. pings from host B to hosts on the 10.1.1.0/24 network....successful4. pings from host B to the Fa0/0 interface on R2....successful5. pings from R2 to host B....successful.The default gateway on host B is not correctly set.What is a supernet?a summarization of classful addressesCCNA 2 - Module 7Refer to the exhibit. If all routers are running RIP version 2, why is there no route for the 192.168.1.32/27 network?Rip version 2 will auto summarize routes by default.Refer to the exhibit. Which two statements are true? (Choose two.)Router1 will install a route to 192.168.0.0/20Router2 will not install a route to 192.168.16.0/20Refer to the exhibit. Which command on which router will allow Router1 to learn about the 192.168.0.0/20 network?Router2(config-router)# version 2What are two reasons to implement RIP version 2 rather than RIP version 1? (Choose two.)RIP version 2 supports VLS M.。
思科第二学期第二章习题答案

1下列哪一个地址可以用来总结网络、、和?2请参见图示。
目的地为网络的数据包会被如何转发?Router1 会执行递归查找,数据包将从 S0/0 接口发出。
Router1 会执行递归查找,数据包将从 S0/1 接口发出。
没有与网络关联的匹配接口,因此数据包将被丢弃。
没有与网络关联的匹配接口,因此数据包将采用“最后选用网关”,从 S0/2 接口发出。
3指向下一跳 IP 的静态路由在路由表中会显示怎样的管理距离和度量?管理距离为 0,度量为 0管理距离为 0,度量为 1管理距离为 1,度量为 0管理距离为 1,度量为 14两个独立子网上的主机之间无法通信。
网络管理员怀疑其中一个路由表中缺少路由。
可以使用哪三条命令来帮助排查第 3 层连通性问题?(选择三项。
)pingshow arptracerouteshow ip routeshow interfaceshow cdp neighbor detail5请参见图示。
为使主机 A 能够连接到网络上的主机 B,应在 Router1 上配置哪种静态路由?ip routeip routeip route S0/0/1ip route S0/0/06Router# show cdp neighbors命令会显示下列哪些内容?(选择三项。
)负载平台可靠性保持时间本地接口7为什么在创建送出接口为以太网络的静态路由时输入下一跳 IP 地址是明智之举?添加下一跳地址将使路由器在转发数据包时不再需要在路由表中进行任何查找。
在多路访问网络中,如果没有下一跳地址,路由器将无法确定以太网帧的下一跳 MAC 地址。
在静态路由中使用下一跳地址可以为路由提供较低的度量。
在多路访问网络中,在静态路由中使用下一跳地址可以使该路由成为候选默认路由。
8请参见图示。
要使 WinterPark 和 Altamonte 路由器能够传送来自每个 LAN 的数据包并将所有其它流量转到 Internet,应该使用哪一组命令来配置静态路由?WinterPark(config)# ip route 0.0.0.0Altamonte(config)# ip route s0/1WinterPark(config)# ip route 0.0.0.0Altamonte(config)# ip route s0/1WinterPark(config)# ip routeAltamonte(config)# ip routeWinterPark(config)# ip routeAltamonte(config)# ip route 0.0.0.0 s0/09当外发接口不可用时,路由表中的静态路由条目有何变化?该路由将从路由表中删除。
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参加考试 - ERouting Chapter 3 - CCNA Exploration: 路由协议和概念 (版本 4.0) 1 下列哪两项正确描述了管理距离与度量的概念?(选择两项。) 错误!未找到引用源。
管理距离是指特定路由的可信度。
错误!未找到引用源。
路由器会首先添加具有较大管理距离的路由。
错误!未找到引用源。
网络管理员无法更改管理距离的值。
错误!未找到引用源。
具有到目的地的最小度量的路由即为最佳路径。
错误!未找到引用源。
度量总是根据跳数确定。
错误!未找到引用源。
度量会根据所采用的第 3 层协议(如 IP 或 IPX)而发生变化。 2 请参见图示。下列关于 R1 如何确定与 R2 之间最佳路径的陈述中,哪一项正确? 错误!未找到引用源。
R1 会将使用网络 A 的 RIP 路由加入路由表,因为 RIP 的管理距离比 EIGRP 大。
错误!未找到引用源。
R1 会将使用网络 A 的 RIP 路由加入路由表,因为 RIP 的路径开销比 EIGRP 低。
错误!未找到引用源。
R1 会将使用网络 B 的 EIGRP 路由加入路由表,因为 EIGRP 的管理距离比 RIP 小。
错误!未找到引用源。
R1 会将使用网络 B 的 EIGRP 路由加入路由表,因为 EIGRP 的路径开销比 RIP 低。
错误!未找到引用源。
R1 会将 EIGRP 路由和 RIP 路由加入路由表,并在它们之间实施负载均衡。 3 下列关于无类路由协议的陈述,哪两项是正确的?(选择两项。) 错误!未找到引用源。
在路由更新中发送子网掩码信息
错误!未找到引用源。
将完整的路由表更新发送给所有邻居
错误!未找到引用源。
受 RIP 第 1 版支持
错误!未找到引用源。
允许在同一拓扑结构中同时使用 192.168.1.0/30 和 192.168.1.16/28 子网
错误!未找到引用源。
减少组织中可用地址空间的大小
4 网络管理员可使用下列哪一条命令来确定路由器是否启用了负载均衡? 错误!未找到引用源。
show ip protocols
错误!show ip route 未找到引用源。 错误!未找到引用源。
show ip interface brief
错误!未找到引用源。
show ip interface
5 存在下列哪两个条件时,使用距离矢量路由协议会比较有效?(选择两项。) 错误!未找到引用源。
网络需要特殊的分层式设计
错误!未找到引用源。
网络必须能快速收敛
错误!未找到引用源。
网络使用的是集中星型拓扑结构
错误!未找到引用源。
网络使用的是平面设计 错误!未找到引用源。
相距最远的路由器之间超过 15 跳
6 路由协议有何作用? 错误!未找到引用源。
用于构建和维护 ARP 表。
错误!未找到引用源。
提供分割和重组数据包的方法。
错误!未找到引用源。
可让管理员设计网络寻址方案。
错误!未找到引用源。
可让路由器之间共享有关已知网络的信息。
错误!未找到引用源。
提供规程,将数据编码和解码为比特,以便转发数据包。
7 下列哪项说法正确描述了距离矢量路由协议的工作情况? 错使用跳数作为唯一度量。 误!未找到引用源。 错误!未找到引用源。
仅在添加了新网络时发送更新。
错误!未找到引用源。
将路由表发送给直连的邻居。
错误!未找到引用源。
将路由更新发送到整个网络。
8 当多个路由协议都有一条通往同一个目的网络的路由时,决定将哪条路由添加到路由表中的依据是什么? 错误!未找到引用源。
最佳度量
错误!未找到引用源。
最少跳数
错误!未找到引用源。
最高可用带宽 错误!未找到引用源。
最小管理距离
错误!未找到引用源。
最低开销
9 为什么快速收敛适合于使用动态路由协议的网络? 错误!未找到引用源。
在网络收敛之前,路由器不允许转发数据包。
错误!未找到引用源。
在网络收敛之前,主机无法访问其网关。
错误!未找到引用源。
在网络收敛之前,路由器可能会做出不正确的转发决定。
错误!未找到引用源。
在网络收敛之前,路由器不允许更改配置。
10 网络必须满足下列哪项条件,才能称为达到收敛? 错网络中的路由器运行动态路由协议。 误!未找到引用源。 错误!未找到引用源。
网络中所有路由器的 IOS 版本必须兼容。
错误!未找到引用源。
网络中的路由器具有相同的路由表。
错误!未找到引用源。
网络中的路由器所了解的路由信息一致。
11 下列关于度量的陈述,哪两项是正确的?(选择两项。) 错误!未找到引用源。
RIP 使用带宽作为度量。
错误!未找到引用源。
OSPF 使用延迟作为度量。
错误!未找到引用
EIGRP 使用带宽作为度量。 源。 错误!未找到引用源。
OSPF 使用基于带宽的开销作为度量。
错误!未找到引用源。
RIP 使用延迟作为度量。
错误!未找到引用源。
EIGRP 使用跳数作为唯一的度量。
12 关于使用静态路由的优点,下列哪两项描述正确?(选择两项。) 错误!未找到引用源。
安全性更高
错误!未找到引用源。
配置路由的工作量更少
错误!未找到引用源。
管理员保持对路由的控制
错误!未找到引
在不断扩展的网络中更容易实施 用源。 错误!未找到引用源。
降低了路由出错的几率
错误!未找到引用源。
提高了路由资源的使用率
13 路由表中显示有下列代码行: R 209.165.201.0/24 [120/2] via 192.168.252.2, 00:00:16, S0/0/0 从该输出中可得出什么结论? 错误!未找到引用源。
目的地为主机 192.168.252.2 的数据包将从连接到网络 209.165.201.0/24 的接口转发出去。
错误!未找到引用源。
当路由器针对同一目的网络配置了多个路由协议时,数值 120 用于确定最佳路径。
错误!未找到引用源。
该路由是通过 ip route 命令手动配置的。
错误!未找到引
192.168.252.2 是生成此输出的路由器上的一个接口。