Pass the Huawei HCIE-Datacom H12-891_V1.0 Questions and answers with ExamsMirror

In Huawei’sVXLAN implementation, the typical mapping betweenVNIs (VXLAN Network Identifiers)andBDs (Bridge Domains)is:

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

This allows properMAC learning and forwardingin the data plane for isolated tenant traffic.

Other mappings (N:1, 1:N, N:M) may be technically possible butnot recommendedor supported in most enterprise deployments.

Correct answer: B. 1:1

In OSPF:

AnNSSA (Not-So-Stubby Area)allowsexternal route injectionviaType 7 LSAs.

These Type 7 LSAs aregenerated by ASBRs inside the NSSA(R4 in this case) when external or direct routes are imported.

ABRs(such as R2) between the NSSA and backbonetranslate Type 7 LSAs into Type 5 LSAsfor flooding into other areas.

Clarification of options:

A: Incorrect — default route is not involved here; it's a specific route (10.1.4.4/32).

B: Correct — R2 translates Type 7 LSAs into Type 5.

C: Incorrect — default route is not being advertised.

D: Correct — R4 imports a direct route and generates Type 7 LSAs for it.

Correct answers: B, D

Intra-Area-Prefix-LSA (Type 9) is used in OSPFv3 to carry IPv6 prefix information for a router or network and is flooded within the area.

Link-LSA (Type 8) is only sent on the local link and is not flooded throughout the area.

Inter-Area-Prefix-LSA (Type 3) and Inter-Area-Router-LSA (Type 4) are also flooded within an area but originate from ABRs, typically for cross-area route advertisement.

That said, Intra-Area-Prefix-LSA is specifically flooded within an area, matching the context of the question directly.

Exact Extract - Huawei HCIE-Datacom OSPFv3 Module:

“Intra-Area-Prefix-LSAs are flooded within the area and advertise the IPv6 prefixes associated with router and network LSAs.”

Understanding the Routing Table Entries on R4

0.0.0.0/0 (Default Route)is installedtwicein the routing table.

TheNextHopvalues for the default route:

10.1.24.1 (GigabitEthernet0/0/1)

10.1.34.1 (GigabitEthernet0/0/0)

Cost:Both routes have a metric (Cost) of10, meaning they areequal-cost routes.

Protocol:ISIS-L1 (Intermediate System to Intermediate System - Level 1) confirms these routes are coming fromIS-IS routing.

Flags:D (Dynamic) means these routes were dynamically learned via IS-IS.

Why is Option D Correct?

Since both routeshave the same cost (10), they are consideredequal-costdefault routes.

The routerwill use both routes in a load-sharingfashion.

The answeris NOT A(Four equal-cost routes) because there areonly twodefault routes, not four.

The answeris NOT B(One default route) because there aretwo default routesin the table.

The answeris NOT C(Two default routes with different costs) because both routes havethe same cost (10).

Real-World Application

Equal-Cost Multi-Path (ECMP):The router can performload balancingacross the two equal-cost paths.

Resilience & Redundancy:If one link fails, the other can take over without re-calculating the entire routing table.

✅Reference:Huawei HCIE-Datacom Study Guide – IS-IS Routing & ECMP Load Balancing

Comprehensive and Detailed In-Depth Explanation:

OSPFv3, which supports IPv6, uses a router ID that is 32 bits in length, similar to OSPFv2. The router ID in OSPF is always a 32-bit number, typically represented in an IPv4 address format (dotted decimal). Although OSPFv3 is designed to support IPv6, itstill relies on a 32-bit router ID for identification, which must be unique within an OSPF domain. The router ID does not change even though the protocol itself supports IPv6 addresses (128 bits).

In Huawei'sSRv6 instruction namingsystem, each letter keyword represents a specific forwarding behavior:

X (Cross): Forwards packets viaspecified Layer 3 interfaces→✅

M (MAC): SearchesLayer 2 forwarding tableforbroadcast/multicast,not unicast→❌

V (VPN): Searches theVPN routing table (VRF)for forwarding →✅

T (Table): Searches aspecific routing table (e.g., user-defined)→✅

Correct answers: A, C, D

Comprehensive and Detailed In-Depth Explanation:

The diagram shows aWAN networkwhereSegment Routing (SR)is used in conjunction with theiMaster NCEcontroller. The network consists ofData Centers (DCs),Branches,Provider Edge (PE)routers, andRoute Reflectors (RR)withinAS 65600. Let's analyze each network technology and its placement in the scenario.

1. BGP-LS (Border Gateway Protocol - Link State):

Application Location:1 (PE to RR)

BGP-LS is used tocollect and distribute network topology informationfrom theIGP (Interior Gateway Protocol)domain.

It enables theiMaster NCE(controller) to learn about the network topology and SR information from PE routers.

The PE routers send theirlink-state informationto theRRusingBGP-LS.

Why Location 1:

The RR collects topology data from PEs and forwards it to the controller for path computation.

2. BGP (Border Gateway Protocol):

Application Location:2 (RR to iMaster NCE)

Standard BGP is used forroute distributionandnetwork connectivity.

The RR usesBGPto exchange route information with thecontroller(iMaster NCE).

Why Location 2:

TheRRaggregates routes and exchanges them with the iMaster NCE for centralized management.

3. MP-IBGP (Multiprotocol Internal BGP):

Application Location:3 (PE to PE)

MP-IBGP is used toexchange VPNv4 and VPNv6 routesbetween PE routers within thesame AS.

It allows PEs toadvertise VPN routesacross thebackbone network.

Why Location 3:

PEs need to communicate VPN-related information within the AS, ensuring end-to-end connectivity between DCs and branches.

4. BGP SR-Policy/PCEP (Path Computation Element Protocol):

Application Location:4 (iMaster NCE to PE)

BGP SR-Policy andPCEPare used by thecontrollertodistribute SR policiesto the PE routers.

TheiMaster NCEcalculates optimal paths and sends the SR policies to PEs viaBGP SR-PolicyorPCEP.

Why Location 4:

The controller programs theSegment Routing pathsdirectly to the PEs for optimal traffic engineering.

Why This Mapping Is Correct:

The mapping is based on theroles and functions of each protocolwithin theSR-based WAN architecture. The controller uses BGP-LS to learn topology, BGP for route reflection, MP-IBGP for VPN route exchange, and BGP SR-Policy/PCEP for path computation and distribution.

A screenshot of a computer AI-generated content may be incorrect.

Comprehensive and Detailed In-Depth Explanation:

ThegRPC-based telemetry protocolutilizesprotocol buffers (.proto files)to define the structure and data format used in communication between a client and a server. In Huawei's telemetry architecture, these files are categorized based on their roles in the data model.

1. RPC Layer:

File:huawei-grpc-dialin.proto

TheRPC layer (Remote Procedure Call layer)handles communication between the client and server.

The filehuawei-grpc-dialin.protodefines thegRPC service interfaces, message structures, and procedures for remote method invocation.

It is essential forestablishing communicationandinvoking telemetry data collection.

Function:Managesdial-in and dial-out connectionsbetween the telemetry client and the server.

2. Telemetry Layer:

File:huawei-telemetry.proto

Thetelemetry layeris responsible forcollecting, packaging, and exporting telemetry data.

The filehuawei-telemetry.protocontains thedata modelused for telemetry reporting, includingstreaming data formatsandtelemetry messages.

It defines how thecollected datais organized and transmitted.

Function:Provides astructured way to export telemetry datain real-time or batch mode.

3. Service Data Layer:

File:huawei-debug.proto

Theservice data layercontains data models related todiagnostics, debugging, and operational data.

The filehuawei-debug.protois used tocollect debugging informationfrom network devices.

This file is crucial fortroubleshooting and monitoring the healthof the system.

Function:Facilitatesdebugging and diagnostic telemetry data collection.

Why This Mapping Is Correct:

The mapping is based on thefunctional role of each layerand thepurpose of each .proto filein the Huawei gRPC-based telemetry architecture.

Correctly identifying the file location is crucial foreffective telemetry configurationanddata collection.

A. The device sends sampled data every second→Correct, since sample interval is 1000ms = 1 second.

B. The subscription mode is static subscription→Correct, as shown by Sub state: PASSIVE. Passive indicates astatic subscription.

C. The IP address of the device is 192.168.56.1→Incorrect— this IP address is thedestination (telemetry collector),notthe device’s own IP.

D. The subscription name is Sub1→Correct, as per Sub name : Sub1.

Correct answer: C. The IP address of the device is 192.168.56.1— this is incorrect because it's actually the collector’s IP, not the device's.

In IPsec, a symmetric encryption algorithm (e.g., AES) is used for encrypting data due to its speed. To securely exchange the symmetric key between peers, asymmetric encryption algorithms (like RSA) are used.

This method ensures:

High performance (due to fast symmetric encryption)

Secure key exchange (asymmetric protection)

Exact Extract - Huawei HCIE-Datacom Guide – IPsec Encryption:

“IPsec uses symmetric algorithms to encrypt data for performance and asymmetric algorithms to securely exchange symmetric keys during IKE negotiation.”