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Each question shows the correct answer and an explanation of why it is right
In special scenarios, when advertising routes to an IBGP peer, a BGP device needs to set the next hop to its IP address to prevent blackhole routes. Which of the following commands can be run in this case?
Comprehensive and Detailed Step-by-Step
Blackhole Route Issue in BGP:
In IBGP, the next hop of a route learned from an EBGP peer is not changed by default. If an IBGP peer cannot reach the next hop, blackhole routes may occur.
To prevent this, the peer next-hop-local command is used to set the next hop to the local router's IP address.
Other Commands:
peer mpls-local-ifnet: Used in MPLS networks to set the next hop as the local interface address.
peer private-nexthop: Allows advertising private IP addresses as the next hop.
peer next-hop-invariable: Ensures the next hop is not modified during route advertisement, which is the opposite of what is required here.
HCIA-Datacom Study Guide, Chapter: BGP Next Hop Behavior
Huawei BGP Configuration Commands
On an IS-IS network, areas are divided by router, and a router can belong to only one are
a. Therefore, an IS-IS router only needs to maintain the LSDB of its area.
Comprehensive and Detailed Step-by-Step
IS-IS Area Division:
IS-IS divides areas by routers, not by links. A router is assigned to a specific IS-IS area, but it can belong to multiple levels:
Level 1: Maintains the LSDB (Link State Database) for the local area only.
Level 2: Maintains the LSDB for the backbone area and exchanges routes between areas.
Behavior of a Level 1-2 Router:
A router configured as Level 1-2 must maintain two separate LSDBs:
One for intra-area routes (Level 1).
One for inter-area routes (Level 2).
Incorrect Statement:
The statement that an IS-IS router only needs to maintain the LSDB of its area is incorrect because Level 1-2 routers maintain LSDBs for both levels.
HCIA-Datacom Study Guide, Chapter: IS-IS Area Structure
Huawei IS-IS Fundamentals
STP ensures a loop-free network but has a slow network topology convergence speed, affecting communication quality. RSTP has made some improvements based on STP. Which of the following improvements is not included?
RSTP improves convergence by introducing changes to the BPDU handling mechanism and port roles. However, RSTP does not rely on a fixed timeout of four Hello intervals for negotiation failure. Instead, RSTP uses a more dynamic mechanism to detect topology changes. The other options describe valid RSTP improvements .
During the DHCP interaction process, the DHCP server and client exchange various types of packets. Which of the following packets is not sent from the client to the server?
The DHCPNAK message is sent by the DHCP server to the client to indicate that the requested configuration is not valid. Messages like DHCPDiscover, DHCPRequest, and DHCPRelease are initiated by the client in the DHCP process .
Which of the following statements regarding OSPF route summarization commands are true?
The asbr-summary command is executed in the global OSPF view to summarize external routes. The abr-summary command is executed in the OSPF area view to summarize routes between areas. By default, the advertise parameter is enabled unless explicitly overridden by the not-advertise option .
The typical characteristics of the AI era are that it focuses on data, explores data value, and improves AI efficiency. Therefore, the core requirement of AI for data center networks is speed, meaning low latency.
AI-driven networks focus on maximizing efficiency by minimizing latency to enhance data processing and decision-making speed. The AI era emphasizes leveraging large data volumes and ensuring rapid data center interconnectivity. This makes low latency a critical requirement for AI-ready data center networks, as highlighted in Huawei's AI and data center network optimization materials .
Border Gateway Protocol (BGP) is a distance-vector routing protocol that implements route reachability between ASs. Which of the following protocol port numbers is used by BGP to establish BGP sessions?
BGP uses TCP port 179 to establish BGP sessions between peers. This is the well-known port designated by IANA for BGP. BGP relies on TCP for reliable, ordered delivery of routing information between autonomous systems. Both the source and destination use port 179 for BGP communications.
5 domains from the Huawei H12-821_V1.0 exam outline, with approximate weightings. Every sample question above is tagged with the domain it comes from
This domain explores core concepts in data communication, tailored for network engineers. It provides a strong basis for comprehending network operations by covering network models, data transmission principles, and different network topologies.
This section explores several routing protocols, their configuration, and troubleshooting techniques, with an emphasis on network engineers. It provides a thorough understanding of network routing processes by covering both external gateway protocols (EGPs) like BGP and internal gateway protocols (IGPs) like OSPF and RIP.
This section, intended for network engineers, looks at switching fundamentals, such as how to build VLANs and use Spanning Tree Protocol (STP). It offers understanding of the fundamental technologies that facilitate effective data transport in local area networks.
Sample question from this domain above: Q3
Focusing on network engineers, this section explores essential network security concepts. It covers firewall implementation, virtual private network (VPN) setup, and the configuration of access control lists (ACLs), equipping engineers with the knowledge to secure network infrastructures.
This section, which is essential reading for network engineers, covers typical network problems, troubleshooting approaches, and performance optimization strategies. It attempts to improve engineers' ability to solve problems to maintain and improve network operations.
Common questions about the exam itself
