1. When upgrading the device software, which of the following descriptions about the operation window time is wrong?

2. What is the core idea of network troubleshooting?

3. If no security policy is configured between firewall domains, or when searching for a security policy. If all security policies are not matched, the default interzone packet filtering action is executed by default is?

4. Which of the description of business priority in DSCP is correct?

5. The DHCP protocol can assign some TCP/IP-related parameter information to the client. In this process, DHCP defines a variety of messages. The encapsulation of these messages is?

6. The definition of OPX is?

7. When configuring MPLS VPNI, the administrator configured the command: interface GigabitEthernet0/0/0 ip binding vpn-instance VPN1 Interface GigabitEthernet0/0/1 ip binding vpn-instance VPN2. Which of the following description is wrong?

8. In the alarm management function of eSight, its alarm levels are divided into the following four types:

9. LDP neighbor discovery has different implementation mechanisms and regulations. Which of the following description of LDP neighbor discovery is wrong?

10. The QoS technique commonly used for congestion avoidance is?

11. The three basic characteristics of an SDN network architecture are:

12. Which of the following description of "packet marking" is incorrect?

13. When configuring a RADIUS server template on a Huawei switch, which of the following options are optional configuration parameters?

14. Different virtual machines can use the VTEP tunnel established by vswitchi to communicate with VXLAN. Then the communication process of VXLAN is: 1 The source VTEP encapsulates the ARP broadcast sent by the source VM into a multicast packet and sends it to the L3 network. 2 After receiving the multicast packet, the destination VTEP learns the mapping relationship between the source VM and VTEP, and forwards the multicast packet to the local VM. 3 Local unicast response. 4 The destination VTEP encapsulates the Vxlan tunnel, establishes a mapping table and encapsulates it, and then unicasts it to the source VTEP. 5 The source VTEP receives the response and establishes the mapping relationship between the target VM and the target VEP, removes the tunnel and forwards it to the source VM. 6 The source VM and the target VM communicate unicast packets through the tunnel.

15. ASPF (Application Specific Packet Filter) is a packet filter based on the application layer. It checks the application layer protocol information and monitors the linked application layer protocol status, and implements a special security mechanism through the Server Map table. Which of the following statement about ASPF and Server map table is wrong?

16. In the MPLS network, the switch will assign the description of the label assignment method, which of the following is correct?

17. The main technical schools of SDN advocate that SDN adopts a layered open architecture. Which technical advocates and defines centralized architecture and Openflow?

18. The dynamic IP address assigned to the client by the DHCP server. Usually there is a certain rental period, which of the following description of the rental period is wrong?

19. Regarding the description of OSPF's neighbor relationship failure, which of the following statements is false?

20. In the firewall interzone security policy, which of the following data flow is not in the outbound direction?

21. Which of the following is the scope of manual setting of VRRP priority?

22. Which of the following commands is used to configure VRRP preemption delay?

23. Which of the following limitations of traditional networks do not include?

24. In the scenario of multi-level RR, a large number of secondary RRs will be connected to the primary RR, which may cause the BGP routing table of the primary RR to overflow. What method can be used to reduce the risk of overflow of the BGP routing table of the level RR?

25. Regarding the difference between NSR and NSF, which is correct?