Huawei Updated H12-821_V1.0 Exam Questions and Answers by mimi

Comprehensive and Detailed In-Depth Explanation:

BFD (Bidirectional Forwarding Detection) detects link failures faster than traditional mechanisms.

Session states during setup:

AdminDown → Initial state (session is administratively disabled).

Down → The session is being established but has not yet exchanged valid control packets.

Init → The session is partially established (one side has detected the peer).

Up → The session is fully operational (not part of the setup process).

Since AdminDown, Down, and Init are involved in session setup, the correct answers are B, C, D.

???? Reference: Huawei HCIA-Datacom Study Guide, BFD Session Establishment and States.

Comprehensive and Detailed Step-by-Step Explanation:

Distance-Vector Protocols:

Distance-vector protocols determine the best path based on the distance to a destination and periodically share the entire routing table with neighbors.

Example: RIP is a distance-vector protocol.

Link-State Protocols:

Link-state protocols share information about directly connected links, enabling routers to build a complete map of the network.

OSPF (Open Shortest Path First) and IS-IS (Intermediate System to Intermediate System) are link-state protocols that use Dijkstra’s algorithm to calculate the shortest path.

Border Gateway Protocol (BGP):

BGP is neither a distance-vector nor a link-state protocol. Instead, it is classified as a path-vector protocol that selects the best path based on attributes such as AS-path, next-hop, and local preference.

References:

HCIA-Datacom Study Guide, Chapter: Routing Protocol Basics

Huawei Networking Fundamentals, Section: Classification of Routing Protocols

The silent-interface command disables the sending of OSPF packets, including Hello packets, on the specified interface, which prevents the establishment of OSPF neighbor relationships. However, the interface can still advertise directly connected routes through other interfaces, making Option C incorrect ​.

By default, Huawei firewalls create security zones named untrust, dmz, trust, and local. These zones facilitate security policies for inbound, outbound, and inter-zone traffic control ​.