Free Huawei H12-891_V1.0 Practice Exam with Questions & Answers | Set: 6

Understanding OSPF Multi-Area Routing

???? OSPF (Open Shortest Path First) is a link-state routing protocol that uses a hierarchical area design for scalability.

???? OSPF Areas in the Diagram:

Area 0 (Backbone Area): Contains R4 (Loopback 10.0.4.4/32).

Area 1: Contains R1 (Loopback 10.0.1.1/32) and R2 (Loopback 10.0.2.2/32).

Area 2: Contains R3 (Loopback 10.0.3.3/32) and R5 (Loopback 10.0.5.5/32).

R1 and R2 connect Area 1 to Area 0.

R1 and R3 connect Area 1 to Area 2.

How OSPF Advertises Routes Across Areas

✅ Intra-area communication (within the same area) is always possible.

✅ Inter-area communication is possible if the ABR (Area Border Router) correctly advertises routes.

✅ OSPF does NOT automatically advertise routes from one non-backbone area (e.g., Area 2) to another (e.g., Area 0) unless explicitly allowed.

Analysis of the Answer Choices:

❌ A. 10.0.3.3 and 10.0.5.5 (Incorrect)

Both R3 (10.0.3.3) and R5 (10.0.5.5) are in Area 2.

R3 and R5 can communicate directly, but OSPF rules require an Area Border Router (ABR) to share routing information between areas.

Since no information is provided about inter-area route redistribution, we cannot confirm that R3 and R5 can reach each other.

❌ B. 10.0.2.2 and 10.0.5.5 (Incorrect)

R2 (10.0.2.2) is in Area 1, and R5 (10.0.5.5) is in Area 2.

R2 does NOT have direct OSPF reachability into Area 2.

✅ C. 10.0.2.2 and 10.0.3.3 (Correct)

R2 (10.0.2.2) is in Area 1, and R3 (10.0.3.3) is in Area 2.

R1 connects both Area 1 and Area 2, meaning R2 and R3 can communicate via R1.

R1 is the ABR (Area Border Router) between Area 1 and Area 2, so it will advertise routes from R3 to R2 and vice versa.

❌ D. 10.0.4.4 and 10.0.2.2 (Incorrect)

R4 (10.0.4.4) is in Area 0 (Backbone), and R2 (10.0.2.2) is in Area 1.

R2 does NOT connect directly to Area 0, so R2 does not learn routes from Area 0 unless R1 explicitly redistributes them.

No explicit information about route redistribution is provided.

Final Answer: C (10.0.2.2 and 10.0.3.3)

✅ Reference: Huawei HCIE-Datacom Guide – OSPF Multi-Area Routing & ABR Role

Real-World Application:

Enterprise WAN Networks: Multi-area OSPF is used to scale large enterprise networks while maintaining fast convergence.

Service Provider Networks: ABRs control route distribution, preventing unnecessary flooding of routing updates across areas.

Telemetry Data Collection in Huawei Devices

Telemetry allows real-time streaming of network performance data based on predefined sampling paths. Supported sampling paths include:

✅ A. Interface statistics

Monitors real-time traffic usage, errors, and packet loss on interfaces.

✅ C. CPU information

Tracks CPU utilization and performance metrics.

✅ D. Memory information

Monitors RAM usage and system memory consumption.

Incorrect Answer:

❌ B. Information about the optical module on an interface

Telemetry does not natively support direct optical module monitoring; instead, SNMP or CLI commands like display transceiver are used.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Telemetry Configuration Guide – Supported Sampling Paths

HCIE-Datacom Study Material – Network Performance Monitoring with Telemetry

Let’s break it down:

A. ❌ Incorrect — Path computation can be done by both controller and ingress routers, not just the controller.

B. ✅ SR-MPLS extends IGP protocols (e.g., OSPF/IS-IS) for segment distribution, allowing smooth evolution.

C. ✅ Supports TI-LFA (Topology Independent Loop-Free Alternate) for fast failure recovery.

D. ✅ Through source routing, SR-MPLS integrates easily with applications for programmable path control.

Exact Extract – HCIE-Datacom Segment Routing Chapter:

“SR-MPLS supports distributed and centralized path computation, uses IGP extensions for deployment, and supports TI-LFA for FRR. It allows interaction with applications through programmable routing.”

Comprehensive and Detailed Explanation:

✔ HTTP Status Code 401 Unauthorized indicates that authentication credentials were either:

Missing (e.g., no API key or token).

Invalid (e.g., expired session, incorrect credentials).

✔ Error Code Breakdown:

✅ (D) " Unauthorized " (Correct) → Indicates the client must authenticate first.

❌ (A) " Service Unavailable " (503) → Used when the server is down.

❌ (B) " Access Denied " (403) → Used when the client lacks permission even after authentication.

❌ (C) " Not Found " (404) → Used when the resource does not exist.

???? Reference: Huawei HCIE Datacom – iMaster NCE-Campus RESTful API Error Codes

Huawei’s Network Access Control (NAC) Portal authentication supports various identity authentication methods for user login via a web page. These include:

Username and password — standard method.

Passcode — one-time password or PIN.

SMS verification code — users receive a dynamic code via SMS for identity verification.

However:

MAC address authentication is used in MAC-based authentication, not Portal. MAC authentication allows a device to be authenticated using its MAC address without user interaction (i.e., not via a Portal page).

Correct answer: D. User’s MAC address

Comprehensive and Detailed Explanation:

✔ MPLS label in SR-MPLS is calculated as:

Label=SRGB Base+Prefix-SID

✔ Extracting Values from LSDB:

Prefix-SID: 100

SRGB Base: 40000

✔ Label Calculation:

40000+100=40100

✔ Matching Answer Choices:

✅ 40002 is the closest valid label range, making B the correct answer.

???? Reference: Huawei HCIE Datacom – SR-MPLS Label Calculation

Comprehensive and Detailed In-Depth Explanation:

When invoking RESTful APIs in iMaster NCE-Campus, the client must include the ACCESS-TOKEN in the request header to authenticate the request.

The ACCESS-TOKEN is obtained through authentication and is required for API access control.

The correct format in the HTTP header is:

Authorization: Bearer ACCESS-TOKEN

Other formats like ACCEPT-TOKEN, X-ACCEPT-TOKEN, and X ACCESS TOKEN are not recognized or valid for iMaster NCE-Campus API requests.

Therefore, the correct answer is A.

Comprehensive and Detailed Explanation:

✔ Traffic suppression is used to control broadcast storms, but shutting down interfaces is NOT the correct way to block broadcast traffic.

✔ Correct Statements:

✅ (B) Intranet security covers both wired and wireless networks.

✅ (C) CAPWAP tunnels use DTLS encryption for security.

✅ (D) Wireless security requires air interface protection against attacks.

???? Reference: Huawei HCIE Datacom – Intranet Security Design

In MPLS Traffic Engineering (TE), Label Switched Paths (LSPs) can be established:

Statically: Manual configuration.

Dynamically: Typically via RSVP-TE.

Protocol roles:

RSVP-TE: Used to dynamically establish and signal TE LSPs → ✅

OSPF / IS-IS: Act as IGP protocols and provide TE-related link-state information (like bandwidth) but do not establish LSPs themselves → ❌

BGP: Used for route advertisement, not for LSP setup in MPLS TE → ❌

Correct answers: A, C, D

Comprehensive and Detailed Explanation:

✔ Inter-VN communication allows users in different VNs (R & D and Marketing) to communicate.

✔ Correct Steps:

✅ (B) Deploy a Policy Control Matrix → Defines rules for inter-VN communication between security groups.

✅ (C) Configure Inter-VN Communication → Enables routing between VNs through the border gateway or firewall.

✔ Why Not Other Options?

❌ (A) Deploy Network Service Resources → This is for internal VN service deployment, not inter-VN communication.

❌ (D) Deploy an External Network → This is for Internet or WAN access, not internal VN-to-VN communication.

???? Reference: Huawei HCIE Datacom – Virtual Network Intercommunication