Huawei H12-891 Online Practice Questions and Exam Preparation

Huawei H12-891 Online Questions & Answers

• Question 271:

  As shown in the figure, switches SWA, SWB, and SWC are all running Rapid Spanning Tree Protocol (RSTP). The ports GE0/0/2 on SWB and GE0/0/1 on SWC have specific port roles. What are these port roles?

  A. Alternative port, Backup port
  B. Backup port, Root port
  C. Root port, Designated port
  D. Backup port, Alternative port
  D. Backup port, Alternative port

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  Explanation

• Question 272:

  Which of the following statements about the IGMP proxy is correct? (Choose three)

  A. The downstream interface of the IGMP proxy device generates multicast relay table entries.
  B. IGMP proxy can detect the link status through the information of the member host joining or leaving the multicast group, and enable rapid switching between the primary and standby device links.
  C. IGMP proxy is typically deployed on devices between hosts that are members of the access device.
  D. The IGMP proxy device cannot send query messages to downstream member hosts in place of the IGMP querier to maintain group membership.
  A. The downstream interface of the IGMP proxy device generates multicast relay table entries.
  B. IGMP proxy can detect the link status through the information of the member host joining or leaving the multicast group, and enable rapid switching between the primary and standby device links.
  C. IGMP proxy is typically deployed on devices between hosts that are members of the access device.

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• Question 273:

  IS-IS is a link-state routing protocol that uses the SPF algorithm for route calculations. As shown in the figure, an area contains both IPv4 and IPv6 services and runs IS-IS for network interconnection. R2 supports only IPv4. Regarding the topology calculation of the network, which of the following statements is correct?

  

  A. By default, IPv6 is not supported because of R2; therefore, in the shortest-path tree formed by the IPv6 network computation, the path from R1 to R4 is: R1璕3璕4
  B. If you want IPv4 and IPv6 networks to compute the same shortest-path tree, the ipv6-enable topology ipv6 command must be used to enable IPv6 multi-topology under the IS-IS process
  C. By default, in the shortest-path tree formed by the IPv6 network computation, R1 reaches R4 through R1璕2璕4; since R2 does not support IPv6, it will drop IPv6 packets upon receiving them, causing traffic loss
  D. By default, IPv4 and IPv6 networks are computed separately and form different shortest-path trees
  C. By default, in the shortest-path tree formed by the IPv6 network computation, R1 reaches R4 through R1璕2璕4; since R2 does not support IPv6, it will drop IPv6 packets upon receiving them, causing traffic loss

• Question 274:

  As shown in the configuration, the administrator configured OSPF, but R1 cannot learn routes for other routing domains. What is the possible cause? (Choose two)

  A. This router does not have an OSPF process number configured
  B. This router is configured with a different area ID than its neighbor router's area ID
  C. This router does not have authentication features configured, but neighbor routers configure authentication features
  D. The declared network address of this router does not match the interface mask
  B. This router is configured with a different area ID than its neighbor router's area ID
  C. This router does not have authentication features configured, but neighbor routers configure authentication features

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• Question 275:

  Compared to IPv4 multicast, which of the following descriptions represents a characteristic of IPv6 multicast?

  A. IPv6 multicast does not use MSDP and dense mode, as it primarily relies on protocols like MLD (Multicast Listener Discovery) for managing group membership.
  B. The first 8 bits of an IPv6 multicast address are always FF (11111111), with all IPv6 multicast addresses starting with this prefix.
  C. IPv6 multicast clients use MLD (Multicast Listener Discovery) instead of IGMPv3 to join multicast groups.
  D. IPv6 multicast load sharing extends the multicast routing rules, but it is not completely independent of RPF (Reverse Path Forwarding) check.
  B. The first 8 bits of an IPv6 multicast address are always FF (11111111), with all IPv6 multicast addresses starting with this prefix.

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• Question 276:

  An LSR (Label Switching Router) supports various label retention modes. Which of the following statements regarding the liberal mode are correct? (Choose two)

  A. An LSR retains labels from a neighboring LSR only when the neighbor is its next hop.
  B. This label retention mode saves memory and label space.
  C. An LSR reserves all labels distributed by its neighbor.
  D. The liberal mode requires more memory and label space.
  C. An LSR reserves all labels distributed by its neighbor.
  D. The liberal mode requires more memory and label space.

• Question 277:

  There is an existing router running OSPF HW1. HW1's interface serial0 is published in area 1. The command nssa default-route-advertise is configured under the OSPF process. Based on the previous description, which of the following options are correct? (Choose two)

  A. When HW1 injects a default route into area 1, HW1's local route table cannot contain a single default route.
  B. HW1 injects a Type 7 default route into area 0.
  C. HW1 injects a Type 7 default route into area 1.
  D. HW1 injects a Type 3 default route into area 1.
  E. When HW1 injects a default route into area 1, HW1's local route table needs to have the default route.
  C. HW1 injects a Type 7 default route into area 1.
  E. When HW1 injects a default route into area 1, HW1's local route table needs to have the default route.

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• Question 278:

  Which of the following issues do DiffServ model-based QoS have? (Choose four)

  A. It involves only single-hop behaviors and does not change the network topology.
  B. Independent resources cannot be provided for users.
  C. It does not change service behaviors. If bursty traffic in a single flow is too heavy, congestion still occurs.
  D. The number of queues is small, and SLA assurance cannot be provided for specific users. As a result, deterministic delay assurance cannot be provided.
  A. It involves only single-hop behaviors and does not change the network topology.
  B. Independent resources cannot be provided for users.
  C. It does not change service behaviors. If bursty traffic in a single flow is too heavy, congestion still occurs.
  D. The number of queues is small, and SLA assurance cannot be provided for specific users. As a result, deterministic delay assurance cannot be provided.

• Question 279:

  During WLAN planning and design, channels 1, 6, and 11 are recommended on the 2.4 GHz frequency band, and channels 1, 5, 9, and 13 are recommended in high-density scenarios. On the 5 GHz frequency band, it is recommended that high-frequency and low- frequency channels of adjacent APs be staggered to prevent overlapping.

  A. TRUE
  B. FALSE
  A. TRUE

• Question 280:

  The data results of a router are as follows, which of the following analysis conclusion is correct?

  

  A. The GEO/0/0 port of R3 is in a different region than the neighbor.
  B. The R3 router's Eth0/0/1 enables both IPv4 and IPv6 ISIS.
  C. R3 is on the link where Eth0/0/0 is Eth0/0/1 of the LEVEL-1 and LEVEL-2 DISC.
  D. R3 router's circuit-level is Level-1-2.
  D. R3 router's circuit-level is Level-1-2.

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