Free Huawei H12-891_V1.0 Practice Exam with Questions & Answers | Set: 5

MPLS Positioning in the TCP/IP Model

MPLS (Multiprotocol Label Switching) operates between the Data Link Layer (Layer 2) and the Network Layer (Layer 3).

✅ MPLS is protocol-independent and supports various network layer protocols (IPv4, IPv6, VPN, etc.) by using labels instead of traditional IP routing.

✅ How MPLS Works:

MPLS assigns labels to packets, allowing fast forwarding based on the label rather than a routing table lookup.

Supports Layer 3 VPNs (L3VPNs), Layer 2 VPNs (L2VPNs), and MPLS Traffic Engineering (MPLS-TE).

✅ Why MPLS is Between Layer 2 and Layer 3?

MPLS adds a label between the Layer 2 (Ethernet, PPP) and Layer 3 (IP) headers, effectively creating a separate forwarding mechanism.

Label Switching Routers (LSRs) forward packets based on labels instead of IP addresses, reducing processing time.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS Technology Guide – MPLS Architecture and Label Switching

HCIE-Datacom Study Material – MPLS Positioning and Functionality in TCP/IP

In Huawei’s VXLAN implementation, the typical mapping between VNIs (VXLAN Network Identifiers) and BDs (Bridge Domains) is:

1:1 mapping — each VNI is uniquely associated with a single bridge domain.

This allows proper MAC learning and forwarding in the data plane for isolated tenant traffic.

Other mappings (N:1, 1:N, N:M) may be technically possible but not recommended or supported in most enterprise deployments.

Correct answer: B. 1:1

Comprehensive and Detailed In-Depth Explanation:

Analyzing the output:

A. The device sends sampled data every second: Correct. The sample interval is 1000 ms (1 second).

B. The subscription name is Sub1: Correct. The subscription name is clearly shown as Sub1.

C. The subscription mode is static subscription: Correct. Since the Sub-state is PASSIVE, it indicates a static subscription.

D. The IP address of the device is 192.168.56.1: Incorrect. The IP address 192.168.56.1 shown in the output is the destination IP where the telemetry data is sent, not the IP address of the device itself.

Comprehensive and Detailed In-Depth Explanation:

When configuring a virtualized campus network on iMaster NCE-Campus, the platform supports automatic delivery of routing policies when connecting to external networks, including the Internet.

This feature ensures that traffic destined for external networks is automatically directed to the appropriate egress points.

The NCE-Campus automatically creates and delivers the default route or specific routes, depending on the network topology and configuration.

This simplifies network management by eliminating the need for manual route configuration on each device.

Therefore, the statement is TRUE.

Understanding OSPF Neighbor States

OSPF (Open Shortest Path First) establishes neighbor relationships through several states:

1️⃣ Down: No Hello packets received.

2️⃣ Init: Router receives Hello packets but its own Router ID is missing in the received packets.

3️⃣ 2-Way: Routers see each other in Hello packets. (Stable state for non-DR/non-BDR routers).

4️⃣ ExStart: Routers start exchanging LSAs but may face MTU mismatches.

5️⃣ Exchange: Routers send Database Description (DBD) packets to synchronize link-state databases.

6️⃣ Loading: Routers exchange Link-State Requests (LSRs) & Updates (LSUs) to fully sync.

7️⃣ Full: Routers are fully synchronized.

Analysis of the Answer Choices

✅ A. For non-DR and non-BDR routers on an Ethernet link, the 2-Way state is acceptable.

Correct: Non-DR/Non-BDR routers remain in 2-Way state since they don’t need to form full adjacency.

✅ B. The Init state indicates that the router has received Hello packets from its neighbors, but the received Hello packets do not contain the OSPF RID of the receiving router.

Correct: If an OSPF router receives a Hello but does not see its own Router ID, it stays in the Init state.

✅ C. The ExStart state indicates that two neighbor routers have inconsistent MTUs or the same OSPF Router ID (RID).

Correct: If MTUs mismatch or RIDs conflict, the DBD exchange fails, causing routers to remain in ExStart state.

❌ D. The Attempt state indicates that the router does not send unicast Hello packets to configured neighbors.

Incorrect:

In Attempt state, routers send unicast Hello packets to manually configured neighbors (common in NBMA networks).

If no Hello responses are received, they remain in Attempt state, but they DO send Hellos.

Real-World Application

OSPF Troubleshooting: Identifying routers stuck in Init or ExStart states can point to MTU mismatches or neighbor misconfigurations.

NBMA Networks (Frame Relay, DMVPN): Manually configured neighbors may stay in Attempt state if Hello packets are lost.

✅ Reference: Huawei HCIE-Datacom Study Guide – OSPF Neighbor States & Troubleshooting

On the 2.4 GHz band, only three non-overlapping channels exist: 1, 6, and 11.

In high-density WLAN scenarios, channels like 1, 5, 9, and 13 can be used with lower transmit power to reduce co-channel interference — though they slightly overlap, they can work in dense deployments when managed properly.

On the 5 GHz band, there are many non-overlapping channels. It’s recommended to stagger high and low channels among adjacent APs to avoid interference.

Correct answer: A. TRUE

From the output:

Tunnel destination IP address: Clearly shown as destination 10.0.1.1 → ✅

Tunnel interface MTU: Shown as The Maximum Transmit Unit is 1500 → ✅

Tunnel interface IP: Shown as Internet Address is 20.1.1.2/24 → ✅

Tunnel source: Tunnel source 10.0.3.3 (LoopBack0) → Not 10.0.1.1 → ❌

Therefore:

A — Correct

B — Correct

C — Correct

D — Incorrect (confuses destination as source)

Correct answers: A, B, C

Understanding HTTP/1.1 Response Headers

???? What is an HTTP Response?

When a web server responds to an HTTP request, it sends an HTTP response message.

The response contains headers, a status line, and a response body.

Elements of an HTTP Response Header:

✅ A. Status Code → Correct

Indicates the response status (e.g., 200 OK, 404 Not Found).

✅ B. Reason Phrase → Correct

Provides a human-readable explanation of the status code (e.g., OK, Not Found).

✅ C. Protocol Version → Correct

Specifies which HTTP version is being used (e.g., HTTP/1.1).

❌ D. Response Method → Incorrect

The HTTP method (GET, POST, etc.) is part of the request, not the response.

NETCONF architecture consists of the following conceptual layers:

Secure Transport Layer – Ensures confidentiality (e.g., SSH, TLS)

Messages Layer – Handles framing and encoding (XML-based)

Operations Layer – Includes < get > , < edit-config > , < commit > , etc.

Content Layer – Carries the actual configuration and state data defined by YANG models

This makes Option D correct.

Exact Extract – Huawei HCIE-Datacom NETCONF Architecture Overview:

“NETCONF is divided into four conceptual layers: secure transport, message framing, operations, and content layers.”