Pass the Huawei HCSP Presales H19-402_V1.0 Questions and answers with CertsForce

In Huawei CloudFabric architecture, the underlay network is defined as a pure IP transport (bearer) network whose primary role is to provide Layer 3 reachability between VTEPs (VXLAN Tunnel Endpoints) . It is designed to be simple, stable, and highly reliable , typically composed of spine and leaf switches running routing protocols such as OSPF, IS-IS, or EBGP .

The statement is false because it incorrectly includes LBs (load balancers) and firewalls as part of the underlay network. In Huawei design principles:

Underlay = physical IP forwarding infrastructure (switch fabric only)

Overlay/services = VAS devices (firewalls, load balancers, etc.)

Firewalls and load balancers are considered service devices (VAS) and are usually connected via service leaf nodes or border leaf nodes , operating in the overlay/service layer , not as part of the underlay forwarding plane.

Additionally, the underlay is typically implemented using a spine-leaf architecture , not traditional three-tier (core/aggregation/access) designs.

Therefore, the statement is FALSE .

In Huawei CloudFabric architecture, the underlay network is the physical IP fabric, while the overlay network is a logical network built on top of it using technologies like VXLAN and BGP EVPN .

Option A is false because the overlay network does not require bare optical fibers . It operates independently of the physical medium and can run over any IP-based underlay (Ethernet, optical, etc.). The overlay abstracts the physical infrastructure.

Option B is correct : the underlay network is transparent to endpoints (servers, firewalls, routers). These devices only interact with the overlay and are unaware of the underlying transport.

Option C is correct : the overlay has its own forwarding plane (VXLAN encapsulation) and control plane (BGP EVPN) , enabling scalable and automated network virtualization.

Option D is correct : the overlay is a logical network built over the underlay , providing tenant isolation and flexible service deployment.

Huawei best practices emphasize decoupling overlay from underlay , ensuring flexibility, scalability, and simplified operations.

Therefore, the correct answer is A .

Comprehensive and Detailed 150 to 200 words of Explanation From Huawei data center:

After rechecking against Huawei’s own materials, the verified multi-select answer is B and D . Huawei documentation for Elastic Load Balance, which is the load-balancing architecture referenced in Huawei cloud/data center designs, states that for Layer 4 traffic using TCP/UDP , incoming traffic is routed only through the LVS cluster . For Layer 7 traffic using HTTP/HTTPS , incoming traffic is routed first to the LVS cluster and then to the Nginx cluster before reaching backend servers. That means Huawei explicitly uses LVS for L4 load balancing and Nginx together with LVS for L7 load balancing.

By contrast, IP ECMP is a Layer 3 equal-cost forwarding/load-sharing mechanism, not an L4-L7 service load balancer in Huawei’s CloudFabric context. Huawei’s ECMP documentation discusses route-based traffic distribution in the IP layer, which is fundamentally different from application/service load balancing.

Huawei CloudFabric is designed with an open and extensible ecosystem , enabling seamless integration with multiple platforms and services across modern data center environments. This openness is a key principle in Huawei’s architecture, ensuring interoperability and flexibility for diverse workloads.

Third-party VAS interconnection (A) is supported to allow integration with value-added services such as firewalls, load balancers, and security appliances, enabling service chaining and enhanced network functionality.

Container platform interconnection (B) is critical in cloud-native environments. CloudFabric integrates with platforms like Kubernetes, allowing automated network provisioning for containerized applications through APIs and SDN control.

Cloud platform interconnection (C) includes integration with cloud management platforms such as OpenStack and Huawei ManageOne, enabling unified orchestration of compute, storage, and network resources.

Virtualization platform interconnection (D) supports platforms like VMware and FusionSphere, allowing dynamic VM-based networking and automated service deployment.

Huawei documentation emphasizes that CloudFabric supports all these interconnection scenarios to deliver full-stack, multi-platform integration , making all options correct.

In Huawei M-LAG design, the peer-link is a critical connection between two M-LAG member devices used for synchronization of control information (such as MAC address tables, ARP entries, and state information) and for forwarding certain types of traffic like broadcast, multicast, and unknown unicast (BUM) traffic when necessary.

However, to prevent traffic loops and duplication , Huawei enforces strict isolation between peer-link interfaces and dual-homed M-LAG member interfaces . Specifically, this relationship is bidirectionally isolated , meaning traffic received from a dual-homed interface is not forwarded to the peer-link and then back to another dual-homed interface, and vice versa.

This bidirectional isolation ensures:

Loop prevention without relying on STP

Avoidance of duplicate packet forwarding

Efficient traffic handling in active-active scenarios

BUM traffic is only forwarded over the peer-link under controlled conditions, not blindly between all interfaces. Huawei CloudFabric best practices emphasize this isolation to maintain stable and predictable forwarding behavior in M-LAG deployments.

Therefore, the correct answer is C (Bidirectionally isolated) .

Huawei data center solutions emphasize the transition toward all-flash data centers as a key enabler of enterprise digital transformation. Traditional HDD-based storage systems cannot meet the performance requirements of modern applications such as AI, big data analytics, cloud computing, and real-time services .

SSD (Solid-State Drive) technology provides significant advantages over HDDs, including:

Ultra-low latency (microseconds vs milliseconds)

High IOPS (Input/Output Operations Per Second)

Better reliability and durability (no mechanical parts)

Lower power consumption and higher density

As a result, SSDs have become the mainstream storage medium in modern data centers, especially in Huawei’s all-flash storage solutions (e.g., OceanStor Dorado) .

All-flash data centers enable:

Faster application response times

Improved user experience

Efficient support for AI and distributed workloads

Simplified storage architecture

Huawei promotes integrating all-flash storage with intelligent lossless networks (RoCE-based) to achieve end-to-end high-performance infrastructure.

Therefore, the statement is TRUE .

Huawei M-LAG 2.0 is designed to provide ultra-fast convergence and high availability in modern data center networks. One of its key enhancements over traditional M-LAG implementations is the ability to achieve fast fault detection and rapid switchover , minimizing service interruption.

In the event of a single point of failure (such as link or device failure), M-LAG 2.0 leverages mechanisms like BFD (Bidirectional Forwarding Detection) and optimized peer-link synchronization to quickly detect failures and redirect traffic. The switchover time is typically around 5 milliseconds , ensuring near hitless failover for critical services.

This ultra-fast convergence is particularly important for applications such as AI workloads, financial systems, and real-time services , where even small delays can impact performance.

Compared to traditional technologies (which may take tens or hundreds of milliseconds), Huawei M-LAG 2.0 significantly improves network reliability, service continuity, and user experience .

Therefore, the correct answer is C (5 ms) .

In Huawei CloudFabric Solution, health check and intelligent O & M are performed across multiple key dimensions to ensure stable, secure, and efficient network operations. These dimensions provide a comprehensive view of the data center network’s health.

Capacity (A): Evaluates resource utilization such as bandwidth, device capacity, and scalability limits to prevent bottlenecks.

Status (B): Monitors the operational state of devices, links, and services (up/down, faults, alarms).

Connectivity (D): Verifies end-to-end network reachability, ensuring that services and tenants can communicate properly across the fabric.

Security policy (E): Checks correctness and consistency of policies such as ACLs, segmentation, and service chaining rules.

Performance (F): Measures latency, packet loss, throughput, and congestion, which are critical in modern workloads like AI and storage.

VM (C) is not considered a core health check dimension at the network level. It belongs more to the compute/virtualization domain rather than network O & M.

Huawei iMaster NCE-FabricInsight uses these dimensions to provide proactive fault detection, root cause analysis, and optimization recommendations , ensuring intelligent lifecycle management of the data center network.