Free Huawei H12-891_V1.0 Practice Exam with Questions & Answers | Set: 4

Understanding the Network Scenario:

R2 is the boundary router between OSPF and IS-IS.

OSPF and IS-IS do not automatically redistribute routes between each other.

R4's loopback (10.1.4.4/32) exists in the IS-IS domain.

To allow R1 (OSPF) to reach R4’s loopback, R2 must redistribute IS-IS routes into OSPF.

Why Option C Is Correct (✅)

✔default-route-advertise in OSPF on R2:

This advertises a default route into the OSPF domain, allowing OSPF routers (R1, R3) to forward unknown traffic to R2.

Since IS-IS routes are not automatically injected into OSPF, this ensures R1 can reach R4.

✔IS-IS Already Has Routes to OSPF

IS-IS routers (R3, R4) already learn routes from OSPF via R2 (assuming route redistribution is properly configured).

No need to run default-route-advertise in IS-IS.

Why Other Options Are Incorrect (❌)

❌A. Run default-route-advertise in both OSPF and IS-IS views on R2

Unnecessary in IS-IS. The IS-IS domain already learns OSPF routes from R2 via redistribution.

Only OSPF needs a default route to forward unknown traffic to R2.

❌B. No configuration is required

Incorrect, because OSPF does not automatically learn IS-IS routes.

A default route or redistribution is needed for R1 to reach R4.

❌D. Run default-route-advertise only in the IS-IS view on R2

Incorrect, because IS-IS already has routing information from OSPF.

The issue is with OSPF not learning IS-IS routes, so the command needs to be in OSPF view.

????Reference:Huawei HCIE Datacom – OSPF and IS-IS Route Redistribution and Interoperability

Comprehensive and Detailed Explanation:

TheHuawei Registration Query Centerallows devices to register and go online automatically in acloud-managed environment.

✔Supported Devices:

Switches✅

Access Routers (AR)✅

Access Points (APs)✅

Firewalls✅

✔How It Works:

Devices obtain theirregistration informationviaDHCP Option 148orpre-configured credentials.

The devices thenconnect to the registration query centerto retrieve configuration and authentication details.

Once authenticated, they goonline and become manageable via iMaster NCE-Campus.

????Reference:Huawei HCIE Datacom – CloudCampus Device Registration

✅Hypertext Transfer Protocol (HTTP) is an application-layer protocolused for:

Accessing web pagesand hypermedia content.

Client-server communication over the internet.

Stateless communication with request-response architecture.

Key Features of HTTP:

Application Layer Protocolin theTCP/IP model.

UsesTCP (Port 80) and HTTPS (Port 443)for secure communication.

SupportsREST APIs, web applications, and cloud services.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Network Protocol Guide – HTTP and Web Services

HCIE-Datacom Study Material – Application Layer Protocols in TCP/IP Model

Let’s break this down step-by-step based on Huawei IS-IS VPN and multi-process behavior.

???? Configuration Summary:

Process 1: IS-IS for the global routing table

Process 2: IS-IS for VPN instance tt

Process 3: IS-IS for VPN instance rr

✅ Option C: Correct

Process 1 contains only global routing information.

The configuration of isis 1 does not include any vpn-instance keyword, meaning it is bound to the global routing table.

It does not interact with VPN routing tables unless explicitly configured with import/export mechanisms or route leaking (which is not shown here).

Huawei Datacom Reference:

“When an IS-IS process is not associated with a VPN instance, it belongs to the global routing table and only maintains global routes.”

(Source: HCIE-Datacom Study Guide v3.0 – Chapter: IS-IS for IPv4 and IPv6, Section: Multi-Instance Routing)

✅ Option D: Correct

Routing information of process 2 is isolated from that of process 3.

isis 2 is bound to VPN instance tt

isis 3 is bound to VPN instance rr

Each IS-IS process in Huawei VRF context maintains independent LSDBs and routing tables, and by default, they do not share routing information unless route leaking or redistribution is configured (which is not shown in the config).

Huawei Datacom Reference:

“IS-IS processes bound to different VPN instances operate independently and do not share routing information.”

(Source: HCIE-Datacom Study Guide v3.0 – Chapter: MPLS L3VPN with IS-IS)

Comprehensive and Detailed In-Depth Explanation:

The statementAis incorrect because enablingDHCP snooping in the VLAN viewonly takes effect on interfaces within that specific VLAN that have DHCP snooping configured. It doesnot automatically apply to all interfaces of the device. Each interface within the VLAN must individually be configured or marked as trusted/untrusted.

B:Correct, as DHCP snooping, when enabled globally without any additional specifications, defaults to processingDHCPv4messages.

C:Correct, as DHCP snooping can protect against DHCP spoofing attacks by marking interfaces astrustedoruntrusted.

D:Correct, enabling DHCP snooping on an interface means it will monitor all DHCP messages on that specific interface.

MP-BGP is an extension of BGP-4 that supports multi-protocol address families such as IPv6, VPNv4, etc. When PE and CE exchange BGP routes, there is no need to create a BGP process per VPN on the CE. The CE typically runs a standard BGP process, while the PE maintains separate VPN routing tables (VRFs).

Exact Extract - Huawei HCIE-Datacom MP-BGP Chapter:

“CE devices use standard BGP, and multiple VPNs can share the same BGP process on the CE. The PE handles VPN route separation through VRFs and MP-BGP.”

Comprehensive and Detailed In-Depth Explanation:

A. When planning paths based on bandwidth:Correct. The available bandwidth of each interface must beset in advanceto allow path planning based on bandwidth requirements.

B. When planning paths based on delay:Correct. To plan paths considering delay, you need to deployTWAMP (Two-Way Active Measurement Protocol)oriFIT (Intelligent Flow Information Telemetry)to measure thereal-time delayon network links.

C. If the controller plans SR-MPLS Policy paths:Incorrect. The controller can planprimary, backup, and load-balanced paths, enablingtraffic distribution across multiple paths.

D. Statically planned SR-MPLS Policy paths:Correct. You canmanually configure load balancingfor the primary path when planning the SR-MPLS Policy path statically.

Comprehensive and Detailed Explanation:

Inter-AS MPLS L3VPN Option BrequiresASBRs to exchange VPNv4 routesusingeBGPwith label information.

Analysis of Inter-AS VPN Solutions:

Option B uses eBGP to exchange labeled VPNv4 routes between ASBRs but does not require MPLS between ASBRs.

Option A does not exchange VPNv4 routes over ASBRs (uses IP routing instead).

Option C uses MP-BGP and requires full MPLS between ASBRs.

Since Option B requires ASBRs to exchange VPNv4 routes, the correct answer is B.

????Reference: Huawei HCIE Datacom – MPLS Inter-AS VPNs

Comprehensive and Detailed In-Depth Explanation:

TheiMaster NCE-IP controllerusesTelemetryto collect real-timedevice running statusinformation efficiently and with low latency.

Telemetry (A):Enables continuousdata streamingto the controller, including network performance and link state information.

Telnet (B):Used for manual device management and not suitable for automated data collection.

BGP-LS (C):Used fordistributing link-state information, but not for real-time performance data collection.

IS-IS (D):AnIGP protocol, not used for collecting device status.

InSRv6 (Segment Routing over IPv6),flavorsare extensions to standard SRv6 instructions that define how theSegment Routing Header (SRH)is handled at specific points:

PSP (Penultimate Segment Pop): Instructs thepenultimate nodeto remove the SRH before reaching the last node →✅

USD (Ultimate Segment Decapsulation): Instructs thefinal segmenttoremove the SRH and IPv6 header, exposing the payload →✅

PSD (Penultimate Segment Decapsulation): Instructs thepenultimate nodeto remove the SRH and deliver the payload →✅

USP (Ultimate Segment Pop)isnot a standard flavorin Huawei SRv6 implementations →❌

Correct answers: A, B, D