Huawei  H12-891 Exam Dumps & Practice Test Questions

Question 1:

When sending telemetry data via gRPC, should TLS be configured to ensure encrypted transmission between devices and collectors?

A. True
B. False

Correct Answer: A

Explanation:

In today’s digital infrastructure, telemetry has become a cornerstone for efficient network monitoring, diagnostics, and performance analysis. Telemetry enables devices such as routers, switches, firewalls, and servers to push real-time metrics and status information to centralized collectors or monitoring platforms. These metrics often include vital details such as system health, bandwidth usage, latency, interface errors, and CPU load. Because of the sensitive nature of this data, especially in enterprise or service provider environments, ensuring secure transmission is critical.

A commonly used transport protocol for telemetry is gRPC (Google Remote Procedure Call). gRPC is an open-source, high-performance framework built on HTTP/2, offering features like multiplexing, flow control, and streaming, which make it ideal for scalable telemetry systems. However, gRPC on its own does not offer encryption. This is where Transport Layer Security (TLS) comes into play.

TLS is a cryptographic protocol designed to secure communication over a network. When TLS is configured, it encrypts all data in transit, protecting it from eavesdropping, tampering, or interception by unauthorized actors. In environments where telemetry data could reveal system configurations, operational behaviors, or performance bottlenecks, encrypting this information is essential to maintaining data confidentiality and integrity.

If gRPC is used without TLS, the data is sent in plaintext, making it vulnerable to man-in-the-middle attacks, particularly when telemetry flows across the internet or untrusted internal networks. TLS ensures that telemetry collectors and devices mutually authenticate and that all communications remain confidential and unmodified.

Option A correctly states that TLS must be configured when using gRPC for telemetry to ensure encrypted and secure data transport. It’s not optional in secure production environments—it’s a best practice and a necessity.

Option B incorrectly implies that TLS is not required. While technically possible to run gRPC without TLS in a lab or trusted environment, this is not advisable for real-world deployments where data sensitivity and compliance requirements are in play.

In conclusion, whenever gRPC is used for telemetry, configuring TLS is critical to maintain secure communication. It protects the telemetry data and ensures that systems transmitting and receiving this information are operating in a trustworthy and secure environment.

Question 2:

Is it mandatory to configure SSH on Huawei network devices before enabling NETCONF?

A. True
B. False

Correct Answer: A

Explanation:

NETCONF (Network Configuration Protocol) is a widely adopted standard defined by the IETF to manage and configure network devices such as routers, switches, and firewalls. It allows both retrieval of configuration data and provisioning of device settings in a structured, programmatic way—often using YANG models to define the data structure. NETCONF is especially useful in automation frameworks, supporting changes at scale with consistency.

One of the fundamental aspects of NETCONF is its reliance on a secure transport mechanism. By design, NETCONF operates over SSH (Secure Shell). SSH provides the necessary encryption, authentication, and session management features required to safely transmit configuration data between a management station and the device.

In the context of Huawei network devices, the implementation of NETCONF strictly adheres to the standard, which mandates that SSH must be enabled and configured prior to activating NETCONF. Without SSH, there’s no secure channel through which NETCONF operations can be executed. As a result, even if NETCONF is enabled at the configuration level, the absence of a working SSH setup will prevent it from functioning.

Option A is correct because SSH acts as the foundational protocol that NETCONF depends on. Before NETCONF can be initiated or accessed remotely, SSH server functions must be configured, which typically includes defining authentication mechanisms, enabling the correct service instance, and applying access control rules if needed.

Option B, on the other hand, is incorrect. It suggests that SSH is not required, which contradicts both industry standards and Huawei’s own implementation guidelines. NETCONF cannot establish a session or exchange data without a secure transport, making SSH a non-negotiable prerequisite.

Furthermore, using SSH not only ensures encryption of data in transit but also provides a layer of authentication, allowing only authorized administrators or systems to push or pull configurations. This is especially important in production networks where configuration changes can have significant operational impacts.

In conclusion, enabling NETCONF on Huawei devices requires prior configuration of SSH. This ensures secure and authenticated communication between the device and management systems, making Option A the accurate choice.

Question 3:

Is the following statement true or false?
"Segment Routing (SR) forwards data packets based on the source IP address."

A. True
B. False

Correct Answer: B

Explanation:

The assertion that Segment Routing (SR) forwards packets based on the source IP address is false. Segment Routing is a next-generation network routing technique that operates using a completely different forwarding model compared to traditional IP-based routing.

Instead of relying on destination or source IP addresses to determine how a packet is forwarded, SR uses segments, which are encoded instructions or labels embedded in the packet header. These segments define the specific path the packet must follow through the network. Each segment can represent a topological instruction, such as going through a particular node, taking a specific link, or even applying a service function at a router.

The core concept behind Segment Routing is the source routing paradigm, where the originator of the packet specifies the exact route or list of segments that should be followed. This eliminates the need for complex routing tables or traditional path selection methods based solely on destination or source IPs.

Segment Routing comes in two major forms:

• SR-MPLS: Uses MPLS labels as segments.

• SRv6 (Segment Routing over IPv6): Uses IPv6 extension headers to encode segments.

In both cases, the forwarding logic is guided entirely by these segments and not by the source IP address. The source IP may still exist in the packet as part of the standard IP header, but it plays no role in how the SR-enabled routers forward that packet.

Why is Option A (True) incorrect? Because it misunderstands how SR operates. While older routing mechanisms might rely heavily on IP headers (source or destination addresses), Segment Routing avoids this dependency to offer a more scalable, programmable, and traffic-engineered approach to network routing. It allows operators to predetermine traffic flows and policies, making the network more responsive to high-level intent and reducing operational complexity.

In conclusion, Segment Routing is not based on source IP-based forwarding. Instead, it forwards packets based on a sequence of segments that define a path, enabling efficient routing and better control over traffic flows.

Question 4:

Is this statement accurate or not? "Segment Routing (SR) leverages source routing principles, and SR-MPLS is a specific implementation that uses MPLS labels for packet forwarding."

A. True
B. False

Correct Answer: A

Explanation:

The statement about Segment Routing (SR) and SR-MPLS is true. Segment Routing is an advanced network routing methodology built upon the source routing concept, where the originator of the packet defines its path through the network using a sequence of instructions called segments.

Unlike conventional IP routing—where routers along the path determine how to forward the packet based on its destination IP address—Segment Routing enables the sender to define an entire or partial path the packet should traverse. These paths are encoded within the packet as a stack of segments, each representing a specific instruction like “go to router X” or “traverse link Y.”

One widely adopted form of Segment Routing is SR-MPLS (Segment Routing with Multiprotocol Label Switching). In SR-MPLS, the segments are implemented as MPLS labels, which are pushed onto the packet’s label stack. As the packet moves through the network, each router reads the top label (segment), performs the corresponding action, and forwards the packet accordingly.

SR-MPLS provides several key benefits over traditional MPLS:

• Simplified control plane: Since the path is pre-encoded by the source, intermediate routers no longer need to maintain complex signaling protocols like LDP (Label Distribution Protocol) or RSVP-TE.

• Efficient traffic engineering: Operators can define traffic flows based on policies, SLAs, or application needs, optimizing bandwidth and reducing congestion.

• Improved scalability: With fewer protocol requirements and control messages, networks can grow more easily without increased complexity.

Thus, Option A (True) is the correct choice because SR-MPLS does indeed use MPLS labels as the mechanism for forwarding and is grounded in the principles of source routing.

Option B (False) is incorrect because it ignores the foundational architecture of SR-MPLS. Not only is SR based on source routing, but SR-MPLS specifically builds upon it by mapping segments to MPLS labels, allowing seamless integration with existing MPLS infrastructure while eliminating the need for traditional signaling protocols.

In essence, SR-MPLS is a modern, scalable, and policy-driven routing approach that uses MPLS labels to guide packets along paths chosen by the source, offering operational simplicity and greater traffic control.

Question 5:

Is it true that VPN instances are not required on Provider Edge (PE) routers when using 6PE or 6VPE for IPv6 transport over an MPLS network?

A. True
B. False

Correct Answer: B

Explanation:

The assertion that VPN instances are not needed on PE routers in 6PE and 6VPE deployments is incorrect. Both 6PE (IPv6 Provider Edge) and 6VPE (IPv6 Virtual Private Edge) are technologies designed to enable IPv6 communication over an IPv4-based MPLS core. These solutions are widely adopted in service provider networks to extend IPv6 services without requiring a native IPv6 backbone.

In these architectures, the PE routers serve as key transition points between the customer-facing IPv6 networks and the MPLS backbone. They must perform label switching and maintain routing information for customer traffic. To do this effectively, VPN instances are essential.

Let’s look at each technology briefly:

• 6PE is typically used in non-VPN scenarios where the goal is to carry IPv6 traffic over an IPv4 MPLS core. Even in this case, the PE routers must maintain a mapping of IPv6 prefixes to MPLS labels, and this is done using MP-BGP (Multiprotocol BGP). The PE routers need to hold a context for these routes, even if it’s not a full VPN instance in the traditional sense. Label distribution and proper forwarding behavior still rely on having per-customer or per-prefix logical separation on the router.

• 6VPE, on the other hand, is explicitly designed for VPN services. It extends the capabilities of 6PE by supporting VRF (Virtual Routing and Forwarding) instances, allowing service providers to offer IPv6 MPLS VPNs over an IPv4 backbone. This absolutely requires the configuration of VPN instances on PE routers, where each customer’s routing table is kept logically separate.

In both methods, even though the core remains IPv4 and no changes are needed to P routers (Provider routers), the PE routers must maintain logical separation of customer data—especially with 6VPE, where per-customer VRFs are essential.

Therefore, the idea that PE routers can function without VPN instances in 6PE or 6VPE networks is false. Without these configurations, the PE routers wouldn’t be able to distinguish between different customer routes or correctly forward IPv6 traffic using MPLS labels.

Thus, Option B is the correct answer. Option A is incorrect because VPN or context-based configurations are mandatory to support the operational logic of both 6PE and 6VPE.

Question 6:

Does the command display current-configuration show the active system configuration stored in RAM on a network device?

A. True
B. False

Correct Answer: A

Explanation:

The statement is true—the display current-configuration command is used to show the running configuration that resides in volatile memory (RAM) on a network device. This is especially relevant on Huawei routers and switches that use the Versatile Routing Platform (VRP) operating system.

When a network device is operational, it maintains two primary types of configurations:

1. Running configuration – This is the active configuration that the system is currently using. It resides in RAM, and all real-time changes made through the CLI are applied here immediately.
   Startup configuration – This configuration is stored in NVRAM and is loaded when the device reboots. Unless changes in the running configuration are explicitly saved, they are not retained after a reboot.

The command display current-configuration provides a comprehensive snapshot of all the current settings that are active at that moment. This includes interface settings, routing protocols, security policies, VLAN configurations, user access controls, and more. It’s a crucial tool for network administrators to validate live configurations, troubleshoot issues, and audit device behavior.

This distinction is particularly important when managing configuration consistency. Any modification—like adding a new static route, configuring an interface, or applying a new ACL—affects only the running configuration unless it's manually saved to the startup configuration using a command such as save.

Understanding this dynamic is essential in real-world networking. For example, if an engineer makes several configuration changes to resolve a problem but forgets to save them, all those changes will be lost if the device is rebooted—potentially causing a service disruption or reverting the device to a previously faulty state.

Therefore, Option A is correct: the display current-configuration command indeed shows the current active settings in RAM. Option B is incorrect because it contradicts the function of this widely used command.

In summary, using display current-configuration is a critical practice for reviewing active configurations and ensuring operational transparency before committing changes permanently to the startup configuration.

Question 7:

In a hot standby high availability (HA) firewall setup, is it accurate to say that heartbeat interfaces can be linked directly or through a switch or router?

A. True
B. False

Correct Answer: A

Explanation:

In a high availability (HA) environment where firewalls are deployed in a hot standby configuration, redundancy is a key element. This setup involves at least two firewalls—typically one acting as the active unit and the other as the standby. The goal is seamless failover in the event the primary firewall fails. This mechanism is supported by a heartbeat system which ensures continuous communication between both firewalls.

The heartbeat interface is specifically designated to exchange these regular status messages. If the standby firewall detects the absence of heartbeat signals from the active unit for a certain period, it interprets that as a failure and promotes itself to the active role. This switchover ensures that traffic flow and services continue without interruption.

A common misconception is that heartbeat interfaces must be directly connected between the firewalls. While direct cabling—such as an Ethernet crossover—is often the simplest configuration, using an intermediary device like a switch or router is entirely valid and frequently used in more complex topologies. For instance, in data centers where physical separation exists between firewall units, directly connecting interfaces may not be practical. Instead, network switches or routers can bridge the communication, enabling the heartbeat signal to be exchanged reliably.

However, network administrators must ensure that this intermediary path does not introduce excessive latency, packet loss, or jitter, as these could disrupt the heartbeat process and trigger unnecessary failovers. Stability and low delay are key factors in maintaining proper HA behavior, regardless of whether a direct link or intermediary device is used.

In conclusion, the assertion in Option A is valid. Fortinet and most enterprise-grade firewalls support both connection methods for heartbeat interfaces. The flexibility to use a switch or router enhances the design versatility of HA deployments. Option B is incorrect, as it imposes an unnecessary limitation not found in real-world implementations.

Question 8:

Is the following statement correct? By default, an OSPF process uses the same ID for both its process ID and domain ID, and you can modify the domain ID using the domain-id command in the OSPF process view.

A. True
B. False

Correct Answer: B

Explanation:

Open Shortest Path First (OSPF) is a dynamic routing protocol commonly deployed in enterprise and service provider networks. It supports multiple routing instances, each identified by a process ID, which is locally significant and used solely for administrative purposes on a single router. This allows network engineers to run multiple OSPF processes on a single device without conflict.

The domain ID, on the other hand, is a distinct concept and typically associated with advanced OSPF features, such as OSPFv3 or Multi-Topology Routing (MTR). The domain ID becomes especially relevant when using multi-area or multi-topology routing or in networks that need to share topology information across different OSPF processes or across MPLS VPN environments.

Contrary to the statement in Option A, there is no default behavior where the domain ID is set equal to the process ID. These identifiers serve separate purposes and are configured independently. Moreover, standard OSPF configurations (especially in OSPFv2, which is used for IPv4 routing) do not include a domain-id command in the typical process configuration view. This command may be available in specific advanced scenarios or in vendor-specific implementations (e.g., MPLS or OSPFv3-based configurations).

Therefore, Option B is correct because it correctly identifies that domain ID and process ID are not inherently linked by default. The idea that one can configure the domain ID using a simple domain-id command from the standard OSPF process view misrepresents how domain IDs are actually implemented and used. This misunderstanding often stems from conflating process-level administration with domain-level routing behavior.

In real-world scenarios, the domain ID is usually configured when there is a requirement for routing information sharing across OSPF domains or between MPLS VPNs, and even then, it’s not tied to the process ID. Understanding this separation is critical for passing the Fortinet FCP_WCS_AD-7.4 exam and for correctly designing scalable OSPF networks.

Question 9:

When operating in DU (Downstream Unicast) label advertisement mode with liberal label retention enabled, does the device preserve all received labels from LDP peers, even if those peers are not the preferred next-hop for a destination?

A. True
B. False

Correct Answer: A. True

Explanation:

In Multiprotocol Label Switching (MPLS) networks, Label Distribution Protocol (LDP) is a standard mechanism that routers use to exchange label mappings for forwarding packets. A fundamental feature of LDP is its ability to work in DU (Downstream Unicast) mode, where labels are distributed only to specific peers that request them.

A critical behavior tied to LDP is label retention mode, which determines how a router treats label mappings from peers that are not the best path (next-hop) to a given destination. There are two main label retention modes: conservative and liberal.

In liberal label retention mode, the router retains label mappings received from all LDP peers, regardless of whether those peers are on the optimal path to the destination. This means the router doesn’t discard the labels, even if it’s not currently using them in the forwarding table. These retained labels stay in the Label Information Base (LIB) but may not be installed into the Label Forwarding Information Base (LFIB) unless the routing table changes.

This approach is highly beneficial in dynamic networks. If the network topology changes—such as a failure in the primary path—the router can quickly switch to an alternative path using the labels it has already retained, without needing to renegotiate with peers. This reduces convergence time and enhances overall resiliency and stability of MPLS operations.

In contrast, conservative label retention mode discards labels from peers that are not on the best path, reducing memory usage but delaying recovery in the event of path failure.

Given this behavior, the correct answer is True: in liberal retention mode, the router retains labels from all peers, regardless of their role as the best next-hop.

Answer B (False) is incorrect because it contradicts the core principle of liberal label retention, which is designed to preserve flexibility and facilitate rapid failover in MPLS networks.

Question 10:

In Huawei’s SD-WAN architecture, does a CPE device automatically choose a Region Route (RR) after coming online without any assistance from iMaster NCE-WAN?

A. True
B. False

Correct Answer: B. False

Explanation:

Huawei’s SD-WAN solution provides centralized, intelligent management of wide area networks by separating the control and data planes. This design allows for dynamic traffic management, simplified configuration, and high levels of automation.

Within this architecture, Customer Premises Equipment (CPE) refers to the edge devices deployed at customer locations to connect with the Huawei SD-WAN backbone. These devices are responsible for implementing forwarding decisions, maintaining tunnels, and enforcing policies.

A key component of Huawei’s SD-WAN is iMaster NCE-WAN, the centralized orchestration and control platform. This system manages everything from device onboarding to route optimization, security policy deployment, and application-level traffic control.

Another important concept is the Region Route (RR), which refers to the regional routing point or anchor that facilitates efficient route selection within and across geographic zones in a multi-region deployment. RRs serve as control nodes that maintain route awareness and path optimization across regions.

When a CPE comes online, it does not independently select an RR. Instead, the selection and configuration process is orchestrated by iMaster NCE-WAN. The controller assesses multiple criteria—such as policy rules, topology information, and network health metrics—before assigning the appropriate RR to the CPE.

This centralized approach ensures consistency, optimization, and enforcement of business-level intent across the network. Without the coordination of iMaster NCE-WAN, the CPE would lack the global network visibility required to make intelligent routing decisions.

Thus, the correct answer is False—a CPE cannot autonomously select a Region Route. It requires instructions from the central controller to do so.

Option A (True) is incorrect because it suggests a level of autonomy that the CPE does not possess in this architecture. The centralized model is a cornerstone of Huawei’s SD-WAN design, providing the intelligence and visibility needed for efficient, policy-driven routing.