Huawei Huawei Certifications H12-891 Questions & Answers

• Question 521:

  As shown in the figure, three switches S1, SW, and SN3, where SWI is the root bridge, and link congestion occurs between SI and SW2, SWD cannot receive the configuration BPDU sent by the root bridge, which spanning tree protection mechanism does the administrator need to configure to prevent the problem caused by link congestion?( Single choice questions).

  A. root protection

  B. PreventS TC-BPDU attacks

  C. BPDU Protection

  D. Loop Protection

  Correct Answer: D

• Question 522:

  The HTTP protocol is based on TCP, so http Flood attacks can be defended against HTTP Flood attacks using the TCP Flood attack prevention method.

  A. True

  B. False

  Correct Answer: B

• Question 523:

  Firewall security policies have the condition for traffic matching to be ?( Multi-select)

  A. apply

  B. Source item security zone

  C. Source item IP address

  D. Message length

  Correct Answer: ABC

• Question 524:

  The most effective way to view device warnings through the CLI is ?

  A. Display alarm

  B. Display current-configuration

  C. Display interface brief

  D. Display clock

  Correct Answer: A

• Question 525:

  Although the STP protocol can solve the loop problem, it affects the quality of user communication due to the slow convergence of the network topology. RSTP has made many improvements to STP, which of the following is not an improvement of RSTP to STP?

  A. In addition to the 3 port states, RSTP vice adds 2 new port roles

  B. Non-root switches running RSTP send configuration BPDUs at intervals specified by Hello Timer, a behavior that is entirely autonomous for each device

  C. RSTP port state specification is divided according to whether the port forwards user traffic and learns the MAC address, reducing the original 5 port states to 3

  D. If a port does not receive a configuration BPDU sent by the upstream device for 4 consecutive Hello Time, the device considers the negotiation with this neighbor to fail

  Correct Answer: D

• Question 526:

  The following statement about OSPF route filtering is incorrect.( Single choice questions).

  A. In the NSSA area, filtering for external route ingestion and advertisement can be configured on ASBR or ABR

  B. Filtering for the three types of LSAs needs to be configured on the ABR across OSPF regions

  C. Interface-based filtering of LSAs allows all LSAs in the inbound and outbound directions except grace LSAs

  D. Based on the link state database, when calculating routes, the fiter-policy import command is used, which only affects the route addition in the route table, and has no effect on the OSPF link state database

  Correct Answer: C

• Question 527:

  The following statement about the Security Alliance SA in IPSec is wrong with ?

  A. SA is uniquely identified by a triple that includes the Security Parameter Inder ,Security Parameter Inder), the source IP address, and the Security Protocol Number (ASESP) used

  B. Use the display ipsec command to view information such as the encryption method used with another IPSEC peer, the traffic of interest, and so on.

  C. IPSec only supports encrypting data using the pair encryption algorithm.

  D. IpSec peers must be at a two-way SA to establish an IPSec VPN connection to close

  Correct Answer: A

• Question 528:

  The basic header length of an IPv6 message is a fixed value.

  A. TRUE

  B. FALSE

  Correct Answer: A

• Question 529:

  As shown in the following figure, a part of the LSDB LSDB of a router LSDB is shown in the first one in the following figure. A new LSP has been received, the second one in the figure below, and the following

  statement is incorrect (single choice).

  A. this router will put the newly received LSP into the LSDB

  B. In the case of a broadcast network, DIS will include summary information for this LSP in the next CSNP message.

  C. This router ignores LSPs received from neighbors

  D. If it is a point-to-point network, the router will send PSNP

  Correct Answer: C

• Question 530:

  OSPF fast convergence is an extended feature to improve the convergence speed of routing, in which PRC works by speeding up routing computation by performing path calculations only on the affected nodes when the network topology changes.

  A. TRUE

  B. FALSE

  Correct Answer: B