1. The concepts of RD and RT are introduced in BGP/MPLS IP VPN network.
Which of the following descriptions about RD and RT are correct? (Multiple choice)

2. A network engineer discovered that a link failure alarm frequently appeared on the interface of a certain device. The interface is an Ethernet optical port.
Which of the following commands can the network engineer use to check the transmit and receive optical power of the interface?

3. The detection mechanism of BFD is that two systems establish a BFD session and periodically send BFD control messages along the path between them. If one party does not receive the BFD control message within a specified time, it is considered that a fault has occurred on the path.
Which of the following reasons will not cause the BFD session to go Down?

4. When the device logs in to other devices as an SSH client and fails to log in using public key authentication, which of the following are possible reasons? (Multiple choice)

5. A network engineer captured a multicast data frame whose destination MAC address is 01-00-5e-00-01-01.
Based on this analysis, which of the following cannot be the destination IPv4 address?

6. A network engineer accidentally deleted the IP address of an interface through the command line.
If he wants to view the deleted IP address, which of the following information should he query?

7. Which of the following operations does a network engineer not need to perform when processing a single-hop BFD session Dom?

8. In a BGP/MPLS IP VPN network, VPNv4 routing transfers carry Export RT values.
Which of the following path attributes does MP-BGP use to carry Export RT?

9. In a BGP/IPLS IP VPN network, the output information of a PE device VPN1 is shown in the figure.
ip vpn-instance VPN1
ipv4-family
route-distinguisher 100:1
vpn-target 100:1 200:1 300:1 export-extcommunity
When the VPIv4 route corresponding to VPN1 is advertised to the remote PE, which VPNs of the remote PE will receive the route? (Multiple choice)

10. MPLS needs to assign labels to messages in advance and establish an LSP before it can forward messages. LSP is divided into static LSP and dynamic LSP.
Which of the following protocols can be used to establish a dynamic LSP? (Multiple choice)

11. The network administrator has deployed the DHCP snooping function on the access switch.
Which of the following solutions can be used to reduce the impact of attackers maliciously applying for IP addresses and causing DHCP Server denial of service? (Multiple choice)

12. There are many types of MAC address entries on the switch.
Which of the following types are manually configured by the user and cannot be aged? (Multiple choice)

13. To support the processing and calculation of IPv6 routes, IS-IS adds a new MLPID in TLV No. 129.
MLPID is an 8-bit field that identifies a network layer protocol message.
Which of the following is the MLPID value for IPv6?

14. The OSPF protocol requires routers in the same area to save the same link state database LSDB. As the number of routes on the network continues to increase, some routers cannot carry so much routing information due to limited system resources. This state is called database overload.
If all routers in an OSPE network are configured with "Isdb-overf1low-limit number 7", which of the following scenarios may cause the router to enter the Overflow state? (Multiple choice)

15. If the migration preparation is insufficient, which of the following problems may occur? (Multiple Choice):

16. On an MPLS network, when a transit device receives an MPLS packet and is ready to swap labels, it finds that the label value after swapping is 0.
In this case, which of the following operations will the device perform?

17. The MPLS architecture consists of the control plane and forwarding plane, each of which contains multiple protocols and entries.
Which of the following tables is used to forward MPLS labeled packets?

18. In the BFD (Bidirectional Forwarding Detection) mechanism, two systems establish a BFD session and periodically send BFD control packets along the path between them. If one system does not receive BFD control packets within a specified period, the path is considered faulty.
Which of the following is NOT a possible cause of the BFD session down event?

19. On a PIM-SM multicast network, a network engineer finds that multicast clients cannot receive multicast data.
Which of the following is not a possible cause of this problem?

20. On a BGP/MPLS IP VPN network, VPNv4 routes carry the export RT.
Which of the following attributes is used by MP-BGP to carry the export RT?

21. On a BGP/MPLS IP VPN network, which of the following are carried when a PE advertises VPNv4 routes?

22. There are multiple types of MAC address entries on a switch.
Which of the following entries are manually configured and cannot be aged out?

23. If the display ospfv3 peer verbose command is run to check OSPFv3 neighbor information, the command output contains information such as the peer router ID, global unicast address of the peer interface, and neighbor status.

24. Which of the following TLVs is added to IS-IS to support multi-topology?

25. On the network shown in the figure, EBGP peer relationships are established between neighboring routers through directly connected interfaces. The AS number is 6500X, where X is the number of the router. Both R1 and R4 have static routes to 192.168.1.0/24, which are imported to BGP through the import-route command.
By default, in the routing table of R3, which of the following is the AS_Path attribute carried in the route to 192.168.1.0/24?

26. BGP allows you to use the filter-policy acl-number import command to filter received routes. The value of ad-number ranges from 2000 to 3999.

27. Port security is achieved by converting the dynamic MAC address learned by the interface into a secure MAC address, including secure dynamic MAC, secure static MAC and sticky MAC.
Which of the following descriptions about secure MAC addresses are correct? (Multiple choice)

28. Which of the following commands can be configured on an IS-IS Level-1-2 device to prevent the Level-1 device from generating a default route?

29. A large Internet service provider needs to shut down the equipment in the computer room for maintenance in batches.
As a cutover project manager, which of the following time points would you prefer?

30. The MPLS architecture is divided into a control plane and a forwarding plane, which contains multiple protocols and tables.
Which of the following tables is responsible for forwarding packets with MPLS labels?

31. When the administrator enables the MPLS LDP function of the device, which of the following commands must be configured first?

32. When a network engineer logs in to a NetEngine AR6120 through the console port, he finds that the password is wrong and cannot log in. If the device can still be logged in through the Telnet account and the user account has the permission to change the console port password, he can log in to the device through Telnet and change the console port password.

33. In a BGP/MPLS IP VPN network, VPNv4 routing transfer will carry RD values.
Which of the following path attributes does MP-BGP use to carry the RD value?

34. The dir command and the Is command are used to display information about all files or specified files on the FTP server, and can also save the information about specified files to the local device.

35. In an MPLS network, data is forwarded based on information such as FIB, MILFE, and ILM.
Among these informations, which of the following options is mainly used for information association?

36. With the increase of business traffic, an enterprise needs to expand the dedicated transmission bandwidth of the backbone network.
Which of the following methods can best meet this demand?

37. In a networking environment where the network is relatively stable and has high requirements for route convergence time, you can specify the OSPF LSA update interval to 0 to cancel the LSA update interval, so that topology or route changes can be immediately published to the network through LSA, thereby speeding up the route convergence speed in the network.

38. Which of the following descriptions about OSPFv3 Link-LSA and Intra-Area-Prefix-LSA are correct? (Multiple choice)

39. NetEngine AR can assign DHCP addresses to clients in the same network segment or different network segments from the router as a DHCP server.
Which of the following reasons will not cause the client to be unable to obtain the correct address?

40. The flexible QinQ function can add different outer tags according to different inner messages.
Which of the following descriptions about the tag addition of flexible QinQ is wrong?