31. Refer to the exhibit. Look at the command output. Assume that there is no other path, and the configuration is correct. What would be the consequences of this situation?
布线的问题
D. configuration problem
如图所示，看到这个命令的输出。假设没有其他的路径配置也没有任何的问题，那么这种情 况的后果是什么?
A. Users in SW1 can ping SW2 but not vice versa.
B. Users in SW2 can ping SW1 but not vice versa.
C. Users in SW1 and SW2 can ping each other.
D. Users in SW1 and SW2 cannot ping each other. Answer: D
32. Refer to the exhibit. Look at the command output. What can you use to prevent this behavior?
如图所示，看到这个命令的输出。怎么能阻止这种行为?
A. UDLD (UniDirectional Link Detection 单向链路检测) B. spanning-tree loopguard C. VTP mode transparent D. switchport mode desirable Answer: A
33. Refer to the exhibit. The Layer 2 network uses VTP to manage its VLAN database. A network designer created all VLANs on the VTP server (switch 1) and it has been advertised through VTP to all other VTP clients (switches 2 through 4). Due to network growth, a network operator decided to add a new switch between switch 1 and switch 3. The network operator has been instructed to use a refurbished switch and use a VTP client. Which three of these
factors should the network operator consider to minimize the impact of adding a new switch? (Choose three.)
如图所示，一个二层网络使用VTP来管理VLAN数据库，一个网络设计师在VTP服务器(交 换机1)上创建所有VLAN，并且用VTP将所有的VLAN传递给所有的VTP客户机(交换机 2,3,4) 。由于网络的扩建，公司决定在交换机1和交换机3之间增加一台交换机。公司使用了 一台翻新的交换机。以下哪三个因素可以减少增加交换机所造成的影响。
A. Pay special attention to the VTP revision number, because the higher value takes the priority.
要注意VTP的修订号，因为修订号高的优先级高
B. Configure all VLANs manually on the new switch in order to avoid connectivity issues.
C. A trunk should be established between the new switch and switches 1 and 3 as VTP only runs over trunk links.
在新交换机和交换机1和3之间运行Trunk
D. Set at least the VTP domain name and password to get the new switch synchronized.
需要设置VTP的域名和密码，以便获得更新
E. An ISL trunk should be established between the new switch and switches 1 and 3, because VTP only runs over ISL. F. Pay special attention to the VTP revision number, because the lower value takes the priority. Answer: ACD
34. Refer to exhibits 1 and 2. In exhibit 1, all users on the LAN segment use router A as the active HSRP router. Router B is the standby router for the HSRP. In exhibit 2, the network management team reported that there is no utilization on the WAN link B. To solve this problem, you decide to change the logical topology of your LAN, but you are not sure about what changes must be made. You must manage HSRP or change it to another protocol in order to provide the most scalable design, automatic redundancy, and load balancing. Which one of these actions would be the best choice?
如图所示，在1组 所有用户是在使用网络中开启了HSRP路由器A和主用路由路由器B是备 用路由器。在2组 网络小组报告网络用户没有使用b的WAN口。要解决这个问题，你决心改 变网络逻辑拓扑，但是你不确定必须这样做。你必须使用HSRP或者使用其他协议来实现挽 网络可扩展性，自动冗余，自动负载。下面哪一个是最好的选择?
A. Use MHSRP, with three users using router A as the default gateway and three users using router B as the default gateway.
B. Keep HSRP and activate PBR to redirect half of the traffic to the other WAN link.
C. Use the backup interface on the WAN link B to provide load balancing for all users.
D. Use GLBP instead, because it provides you with up to three MAC addresses for the same default gateway virtual IP address.
E. Use GLBP instead, because it provides you with up to four MAC addresses for the same default gateway virtual IP address.
使用GLBP，因为他可以提供4个MAC地址相同的默认网关的虚拟地址
Answer: E
35. Refer to the exhibit. Users from the Engineering VLAN complain that every time Business VLAN users have a network connectivity issue, the Engineering VLAN users usually have problems experiencing slow response or network connectivity problems. After troubleshooting, an unauthorized switch 2 was found. This unauthorized switch has been a regular problem, assuming the root bridge function under the spanning-tree domain and causing the Engineering VLAN to be unstable. Which three of these actions could be suggested to fix the problem?
如图所示，工程VLAN用户总是抱怨每次连接上商务VLAN用户时有问题。工程VLAN的用 户经常遇到网络缓慢和网络连接问题。排除故障后，发现一个没有授权的交换机2。这个没 有授权的交换机有规律的出问题， 假设这个交换机在STP中作为工程VLan的根桥， 并造成工 程VLAN的不稳定，下面哪三个问题可以解决这个问题?
A. Upgrade Spanning Tree Protocol to Rapid Spanning Tree Protocol.
升级成快速生成树协议(RSTP)
B. Change Business VLAN PCs to switch 1 and switch 4.
C. Force the root bridge to be switch 2, instead.
D. Adjust spanning-tree timers (max-age and forward-delay).
E. Shut down all unused ports.
关闭没有使用的端口
F. Use MSTP to separate the Engineering VLAN from the Business VLAN to optimize spanning-tree convergence time within each VLAN
使用MSTP 分割工程VLAN和商业VLAN 以优化每个生成树的收敛时间
Answer: AEF
36. The EtherChannel between your LAN switch and the Internet router is not load-balancing efficiently. On the switch, there are several workstations with valid IP ranges. Which load-balance algorithms can you use in the switch in order to optimize this load balancing?
在你的网络交换机之间使用的以太通道但是没有开启负载均衡，有一些工作站的IP地址范 围，你可以怎么配置交换机来实现负载均衡?
(Choose four.) A. source IP address B. destination IP address C. per-packet load balance D. destination MAC address E. source MAC address
Answer: ABDE 
37. Before inserting a new switch in the network, the network administrator checks that the VTP domain name is correct, the VTP mode is set to server, and revision is lower than the switches in the network. The administrator then configures interfaces and trunks, erases existing VLANs, and connects the switch to the network. Following that procedure, there is no connectivity in the network. What is a possible cause of this problem?
之前在网络中加入了一个新的交换机，网络管理员检查VTP域名是正确的。VTP模式设置为 服务器，修订号也比其他的交换机低。管理员配置接口和Trunk。清空了所有的VLAN后吧 交换机连接入网络。经过这些操作，交换机没有任何的网络连接。这是什么问题?
A. Because the configuration revision of the new switches is lower than the rest of the network, it can change the VLAN database of the other switches.
B. As a VTP server, the new switch deleted all VLANs of the network.
C. Erasing VLANs increases the VTP configuration revision.
清空VLAN 会影响到VTP的修订号
D. Since the configuration revision of the network is higher than the new switch, the VLAN database was automatically synchronized.
Answer: C
38. The network administrator wants to enable an EtherChannel between two switches in "on" mode. The administrator connects the cables and enables the interfaces, but while configuring the EtherChannel in the first switch, a spanning-tree loop was detected. Which two of these procedures can avoid this problem? (Choose two.)
网络管理员想在”on”模式下在两台交换机之间开启以太通道， 管理员用线路连接在交换机的 接口上。但是在配置第一台交换机的以太通道时。有一个生成树环路已经产生了。那两个措 施能够避免这个问题?
A. Configure the EtherChannel as "desirable" first. 配置以太通道的模式为“desirable”
B. Assign all interfaces to the same VLAN.
C. Disable PortFast on the interfaces in the EtherChannels.
D. Disable all interfaces first. F. Fix cabling problems. 
Answer: AD
39. Customer X has a hub-and-spoke Frame Relay network, with a central office and two branch offices (RemoteA and RemoteB). Each location has only one physical link to the Frame Relay cloud and RemoteB has a router that is not a Cisco router. Since the installation, there is no connectivity between RemoteB and the central office. What is a possible solution to this issue?
首先关闭这些接口
E. Fast Ethernet and Gigabit Ethernet ports cannot be assigned to the same EtherChannel.
客户X 有一个HUBSPOKED的帧中继网络来连接中心办公室和两个分支办公室(A和B) ， 每个地方有一个物理线路连接到帧中继网络，B 有一个路由器不是CISCO的，安装后不能 建立B和中心办公室之间的链接，怎么可以解决这个问题?
A. Because Frame Relay IETF encapsulation is only configurable at interface level, you must use IETF encapsulation on all routers.
B. This is not a possible scenario. A dedicated Frame Relay link to RemoteB is mandatory at the central office.
C. The router at RemoteB must be replaced by a Cisco router.
D. Use Frame Relay IETF encapsulation on a per-VC basis on the central office router.
在中心办公室使用IETF来封装帧中继，在没有一个PVC上。
E. There is a problem in the Frame Relay cloud, because Cisco routers are compatible with IETF Frame Relay.
Answer: D
40. Refer to the exhibit. There are two sites connected across WAN links. All intersite and intrasite links always have the same routing metric. The network administrator sees only the top routers and links being used by hosts at both LAN A and LAN B. What would be two suggestions to load-balance the traffic across both WAN links? (Choose two.)
如图所示，都过WAN链路连接的两个网络。所有的内部路由和内部链路的度量值都是一样 的，网络管理员发现只有上面的路由器和线路被用来连接A和B。 ，怎么做能让网络可以负载 均衡?
A. Make HSRP track interfaces between the edge and core routers.
用GLBP替换HSRP
B. Replace HSRP with GLBP.
C. Add crossed intrasite links: R1-R4, R2-R3, R5-R8, and R6-R7.
增加交叉备份链路在：R1-R4, R2-R3, R5-R8, R6-R7
D. Make R3 and R8 have lower HSRP priority than R1 and R7.
E. Replace HSRP with VRRP.
Answer: BC