Huawei H12-891 Online Practice Questions and Exam Preparation

Huawei H12-891 Online Questions & Answers

• Question 601:

  Regarding how the device handles messages in the MPLS network model, which of the following descriptions is incorrect?

  A. The label forwarding path (LSP) is determined and established by various protocols during message forwarding, and the label is never removed on the LSR.
  B. LSR
  C. LER and LSR both use labels.
  D. For IP packets entering the MPLS domain, the device discards them.
  A. The label forwarding path (LSP) is determined and established by various protocols during message forwarding, and the label is never removed on the LSR.

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• Question 602:

  Regarding BGP's recognized optional attributes, which of the following descriptions is correct? (Choose two)

  A. Must be passed between BGP neighbors
  B. All BGP routers must be recognized
  C. There is no requirement to be present in the Update message, and you can decide whether to add it to the Update message on a case-by-case basis
  D. The BGP router cannot recognize the attribute
  B. All BGP routers must be recognized
  C. There is no requirement to be present in the Update message, and you can decide whether to add it to the Update message on a case-by-case basis

• Question 603:

  In the CloudCampus public cloud scenario, if deployment through the Huawei registration query center is used, you do not need to configure DHCP Option 148 on the DHCP server of the campus network.

  A. TRUE
  B. FALSE
  A. TRUE

• Question 604:

  Which of the following description about the LDP LSP establishment process is correct? (Choose two)

  A. By default, LSRs for the same FEC can receive label mappings only from the optimal next hop, not from the non-optimal next hop.
  B. When a network topology change causes the next-hop neighbor to change, the liberal label retention method is used. LSR can quickly rebuild the LSP by directly using the labels sent by the original non-optimal next-hop neighbor. Liberal retention needs more memory and label space.
  C. In the DoD mode of label publishing, for a specific FEC, the LSR does not need to obtain a label request message from upstream to distribute the label.
  D. The process of establishing an LSP is actually to bind the FEC to the label and advertise this binding to the upstream LSR.
  B. When a network topology change causes the next-hop neighbor to change, the liberal label retention method is used. LSR can quickly rebuild the LSP by directly using the labels sent by the original non-optimal next-hop neighbor. Liberal retention needs more memory and label space.
  D. The process of establishing an LSP is actually to bind the FEC to the label and advertise this binding to the upstream LSR.

• Question 605:

  The means of a LAND attack is that the attacker sends a SYN packet message with the same source and destination addresses to the target host. The source port and the destination port are the same, and the receiver waits for the final ACK packet to be sent. The connection is always in a semi-connected state, resulting in a waste of resources due to the limited TCP reception.

  A. True
  B. False
  A. True

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  Explanation

• Question 606:

  Which of the following description about 802.1S deployment characteristics is correct?

  A. All VLANs share a spanning tree instance
  B. Multiple bridges share a spanning tree instance
  C. Each VLAN has one spanning tree instance
  D. Multiple VLANs share a spanning tree instance
  D. Multiple VLANs share a spanning tree instance

• Question 607:

  What are the following techniques for improving MPLS BGP VPN reliability? (Choose four)

  A. Dual-home networking is configured at the access layer
  B. VPN Fast Reroute (FRR)
  C. VPN Graceful Restart (GR)
  D. PE-CE Fast Reroute (FRR)
  A. Dual-home networking is configured at the access layer
  B. VPN Fast Reroute (FRR)
  C. VPN Graceful Restart (GR)
  D. PE-CE Fast Reroute (FRR)

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  Explanation

• Question 608:

  Regarding the description of the Hello message in the PIM-SM protocol, which statement is incorrect?

  A. Hello messages are sent to multicast address 224.0.0.5
  B. Hello messages are used to elect the DR on multi-router segments
  C. Routers periodically use Hello messages to stay in contact
  D. In a PIM-SM network, a newly started multicast router uses Hello messages to discover neighbors and maintain neighbor relationships
  A. Hello messages are sent to multicast address 224.0.0.5

• Question 609:

  QinQ technology is a method that extends the VLAN space by adding an additional 802.1Q tag to VLAN frames. Regarding QinQ, which of the following statements is incorrect?

  A. Basic QinQ is implemented based on interface orientation
  B. QinQ increases the number of VLANs to 4095 ?4095
  C. Flexible QinQ can classify user VLANs more granularly based on different inner-layer tags and different outer-layer tags D. QinQ technology enables private VLANs to pass through the public network
  B. QinQ increases the number of VLANs to 4095 ?4095

• Question 610:

  What are the reasons why a BGP connection goes down after it is successfully established?

  A. The wrong BGP packet was received
  B. A mandatory attribute in the route update packet is missing
  C. Open message negotiation failed
  D. After the BGP connection is established, the Keepalive message is not received within the negotiated HoldTime
  C. Open message negotiation failed