H19-402_V1.0 Sample Questions Answers

In Huawei CloudFabric design, M-LAG (Multi-Chassis Link Aggregation) is widely used to provide active-active forwarding and high availability at the access and border layers. When border leaf nodes are deployed in an M-LAG pair, they typically connect to upstream PE (Provider Edge) devices in a dual-homing (square topology) manner, ensuring both link-level and device-level redundancy.

However, Huawei design guidelines clearly state that an interconnection link (commonly called a peer-link or bypass link) between M-LAG devices is mandatory. This link is essential for synchronization of forwarding states, MAC address tables, ARP/ND entries, and control plane information between the two devices. It also ensures proper traffic forwarding in failure scenarios, such as when one device loses its uplinks but remains operational.

Without this peer-link, traffic consistency and loop prevention mechanisms cannot function correctly, leading to potential traffic loss or loops. Therefore, even in dual-egress scenarios with PE devices, the bypass/peer link is still required.

Hence, the statement is FALSE.

In Huawei CloudFabric and virtualization-based network models (such as OpenStack Neutron or SDN-based fabrics), the relationship between logical switches (VXLAN networks/BDs) and subnets is not strictly one-to-one .

A logical switch (VXLAN network / BD) can be associated with multiple subnets , allowing different IP segments to coexist within the same Layer 2 broadcast domain. This is commonly used in scenarios such as:

Multi-tenant environments

Gradual IP migration

Hybrid IPv4/IPv6 deployments

Similarly, while a subnet is typically mapped to a specific logical network, the architecture does not strictly enforce a rigid one-to-one constraint in all implementations. Huawei designs emphasize flexibility and scalability , allowing logical network abstractions to support diverse service requirements.

In practical CloudFabric deployments:

A BD/VNI (logical switch) = Layer 2 domain

Multiple subnets (Layer 3) can be configured over it using VBDIF interfaces

Therefore, the statement is FALSE , as the relationship is not strictly limited to one-to-one mapping.

In Huawei CloudFabric architecture, service integration and flexible deployment of security devices such as firewalls are key design principles. Firewalls can be deployed in multiple ways depending on service requirements, traffic patterns, and scalability considerations.

Firewalls can be connected to:

Service leaf nodes : These are dedicated nodes used for service insertion (e.g., firewall, load balancer). Traffic can be steered through these nodes using policy-based routing or service chaining.

Border leaf nodes (combined with service leaf role) : In some designs, border leaf nodes (which connect to external networks such as WAN or Internet) can also integrate service functions, including firewall connectivity. This reduces hardware requirements and simplifies deployment.

Huawei supports both centralized and distributed service deployment models , allowing firewalls to be flexibly inserted into the network fabric. Integration is typically achieved using VXLAN, EVPN, and service chaining technologies , ensuring seamless traffic steering and policy enforcement.

This flexibility enhances:

Network scalability

Security enforcement

Operational simplicity

Therefore, the statement is TRUE .

In Huawei CloudFabric solutions integrated with OpenStack, Neutron is the key component responsible for network service management and integration with external network controllers such as iMaster NCE-Fabric .

Neutron provides APIs for creating and managing network resources such as:

Networks (VXLAN/BD)

Subnets

Ports

Routers

iMaster NCE-Fabric integrates with Neutron via northbound APIs , allowing it to automatically translate cloud network requests into underlay and overlay configurations (e.g., VXLAN, EVPN, routing policies) on physical network devices.

Other components:

Nova (A) manages compute resources (VM lifecycle)

Keystone (B) handles authentication and identity services

Cinder (C) provides block storage services

These components do not directly interact with network controllers for fabric provisioning.

Huawei emphasizes tight integration between Neutron and iMaster NCE-Fabric to enable automated, policy-driven network deployment , which is essential for cloud data center operations.

Therefore, the correct answer is D (Neutron) .

In Huawei CloudFabric architecture, a PoD (Point of Delivery) or site is defined as an independent network fault domain under the management of the SDN controller (such as iMaster NCE-Fabric). This design is fundamental for large-scale data center deployments, ensuring clear fault isolation, simplified management, and scalable expansion.

Each PoD typically consists of one or more spine-leaf fabric architectures , which provide high-bandwidth, low-latency, and horizontally scalable connectivity. Within a PoD, all devices operate under a unified control and policy framework delivered by the controller. If a failure occurs within a PoD, it is contained and does not affect other PoDs, thereby improving overall network reliability.

Huawei recommends this modular design approach to support multi-data center deployments, disaster recovery, and service expansion. Multiple PoDs can be interconnected to form a larger cloud fabric, while still maintaining independent fault domains.

Therefore, the statement accurately reflects Huawei CloudFabric design principles and is TRUE.

In Huawei CloudFabric and cloud platform architectures (such as those integrated with ManageOne and OpenStack ), the concept of a tenant is used to logically isolate resources such as network, compute, and storage . It is correct that one department can be treated as a tenant , and an enterprise can have multiple tenants representing different departments or business units.

However, the statement is false because it incorrectly claims that the entire enterprise data center can be managed by one tenant administrator . In Huawei’s design:

Each tenant has its own administrator , responsible only for that tenant’s resources.

A higher-level role, such as a cloud administrator or system administrator , manages the entire data center infrastructure across all tenants.

This separation ensures:

Multi-tenancy isolation

Security and access control

Clear responsibility boundaries

Huawei emphasizes role-based access control (RBAC) , where tenant admins cannot manage resources belonging to other tenants or the entire infrastructure.

Therefore, the correct answer is FALSE .

According to Huawei data center network design best practices, server access layer design emphasizes high reliability, scalability, and simplicity. Options A, B, and D correctly reflect Huawei recommendations. The number of leaf nodes is indeed determined by server scale and port requirements. Device selection must consider advanced features such as microsegmentation and IPv6 readiness. Additionally, bandwidth planning (downlink server access and uplink oversubscription ratios) is a critical design factor.

However, option C is incorrect. While M-LAG and standalone modes are commonly used in modern data center designs, stacking is generally not recommended in CloudFabric architectures. Huawei discourages stacking in spine-leaf fabrics because it introduces control plane complexity, reduces network scalability, and may create larger fault domains. Instead, M-LAG is preferred as it provides active-active forwarding, better fault isolation, and supports smooth upgrades without impacting services.

Therefore, stating that stacking is recommended is incorrect, making option C the false statement.

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 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 .

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

Huawei data center materials describe a high-performance network using core technical indicators such as high throughput, low latency, and zero packet loss . These are the actual network characteristics used to evaluate whether a data center fabric can efficiently support AI computing, storage traffic, and east-west service communication. In Huawei’s intelligent lossless network design, the purpose is to build a fabric that forwards traffic at high speed, minimizes delay, and prevents packet loss under heavy load.

By contrast, Higher GPU computing power is not a direct network characteristic. It is an effect or business benefit that can result when the network performs well. Huawei explains that intelligent lossless networking improves AI cluster efficiency and helps computing resources operate more effectively, but GPU power itself belongs to the computing layer, not the network feature set. The network supports better GPU utilization; it does not define GPU computing power as one of its own characteristics.

Therefore, the correct answer is B .

The statement is false due to an incorrect description of in-band management communication .

Huawei iMaster NCE-Fabric indeed supports both in-band and out-of-band deployment modes , but the interfaces used are misrepresented:

In in-band mode , iMaster NCE-Fabric uses southbound interfaces (not northbound) to communicate with switches over the service network . These southbound interfaces are responsible for delivering configurations and collecting device information.

In out-of-band mode , the description is correct: the controller connects to device management interfaces via a dedicated management network , ensuring separation from service traffic.

The confusion arises because:

Northbound interfaces are used for communication between the controller and upper-layer systems (e.g., cloud platforms like OpenStack or ManageOne).

Southbound interfaces are used for communication between the controller and network devices .

Huawei architecture strictly separates these roles to enable clear control-plane layering and automation .

Therefore, because the statement incorrectly mentions northbound interfaces in in-band mode , the correct answer is FALSE .

In Huawei M-LAG design, strict requirements ensure stability and consistency between the two participating devices. Option A is false because M-LAG must be established between devices of the same type and model (or at least fully compatible models) . This ensures consistent forwarding behavior, synchronization of MAC/ARP tables, and proper operation of the peer-link and keepalive mechanisms. Using different device types is not supported and may lead to instability.

Option B is correct : unidirectional isolation is relevant only for dual-homed scenarios. If a device is single-homed, this mechanism is not applied.

Option C is correct : the peer-link is a critical connection between M-LAG peers and is typically configured as an Eth-Trunk (link aggregation) to ensure high bandwidth and redundancy.

Option D is also correct : peer-link interfaces are dedicated and cannot be used for other services, ensuring reliable synchronization and control-plane communication.

Huawei best practices emphasize homogeneous device deployment for M-LAG to guarantee predictable and stable operation.

In Huawei CloudFabric VXLAN architecture, distributed gateway networking is designed to overcome the limitations of centralized gateway models by pushing Layer 3 gateway functionality down to leaf nodes .

Options B, C, and D are all true advantages of distributed gateways. B highlights deployment flexibility, where a leaf can act as both Layer 2 and Layer 3 VXLAN gateway, enabling efficient east-west traffic forwarding. C and D emphasize improved scalability: each leaf only maintains local ARP/MAC entries , avoiding the bottleneck of a centralized device learning all endpoints. This significantly reduces resource consumption and enhances horizontal scaling.

Option A , however, describes a characteristic of centralized gateway architecture , where inter-subnet traffic is handled by a central node. This approach leads to suboptimal forwarding paths and potential performance bottlenecks, which distributed gateways are specifically designed to eliminate.

Huawei best practices strongly recommend distributed VXLAN gateways for modern data centers due to their scalability, optimal traffic paths, and reduced resource pressure .

Therefore, the correct answer is A .

Huawei CloudFabric supports multiple data center interconnection (DCI) solutions to meet different scalability and geographic deployment requirements.

Multi-PoD (A) is supported and is used within a single data center to divide it into multiple Pods for modular expansion. It enables large-scale resource pooling while maintaining consistent architecture and simplified management.

Multi-Site (C) is a key CloudFabric capability, allowing multiple geographically distributed data centers to interconnect. This supports disaster recovery (DR), geo-redundancy, and workload migration , often implemented using EVPN/VXLAN across sites.

Multi-DC (D) is a broader concept encompassing interconnection between multiple data centers, including active-active and active-standby designs. Huawei supports this through DCI solutions integrated with CloudFabric , ensuring seamless service continuity.

Multi-VPC (B) is not a standard Huawei CloudFabric multi-DC interconnection model; it is more commonly associated with public cloud networking concepts rather than Huawei’s data center fabric architecture.

Therefore, the correct answers are A, C, and D , which represent the supported multi-data-center interconnection solutions in Huawei CloudFabric.

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.