H12-891_V1.0 HCIE-Datacom V1.0 Questions and Answers

IGP Metric Design in Enterprise WANs

In anenterprise bearer WAN, routingmetrics determine path selection. Theaggregation layerconnects multiple access-layer devices to the core network, so it should have alower metricto:

✅Ensure traffic is forwarded through higher-capacity aggregation links instead of lower-bandwidth access links.

✅Optimize traffic flow, reduce congestion, and improve network efficiency.

✅Enhance reliability by preferring more stable aggregation links.

IGP Routing Protocols Considerations:

OSPF: Lower cost values indicate preferred paths.

IS-IS: Lower link metrics result in preferred forwarding paths.

Reference from Huawei HCIE-Datacom Documentation:

Huawei IGP Design Guide – Enterprise WAN Routing Optimization

HCIE-Datacom Training Material – Metric Calculation and Path Selection in OSPF/IS-IS

Comprehensive and Detailed In-Depth Explanation:

In large- and medium-sized campus networks,Multi-mode authenticationis commonly used for PCs connected to IP phones. This is because multi-mode authentication allows:

Multiple authentication methods on the same interface,such as MAC address authentication for the IP phone and802.1X authentication for the PC.

This setup is ideal for scenarios where both devices share a single network port but require different authentication mechanisms.

MAC address authentication (A)and802.1X authentication (B)individually cannot accommodate both devices efficiently.

Portal authentication (D)is mainly used for guest access and is not practical for IP phone and PC connections.

In OSPF (Open Shortest Path First), routers connected over broadcast networks (like Ethernet) elect aDesignated Router (DR)andBackup Designated Router (BDR).DR election is based on theinterface priority. If the priority is set to0, the routercannot become a DR or BDR.

Whenboth routers have a priority of 0,no DR or BDR will be elected, and since the election fails, the neighbor relationship between the two routers willnot advance beyond the 2-Way state. In this state, the routers acknowledge each other but do not exchange routing information in detail (as they only form full adjacency with the DR/BDR).

Therefore, the OSPF neighbor relationship remains in the2-Way state.

Understanding iMaster NCE-Campus Terminal Identification

Huawei'siMaster NCE-Campusis anAI-driven network managementplatform forcampus networks.

????Terminal Identification Features in iMaster NCE-Campus

Identifies device type(e.g., Laptop, Mobile, IoT device).

Detects Operating System(Windows, Linux, Android, iOS).

Determines manufacturer information(Huawei, Apple, Cisco, Dell).

UsesAI-based profilingto continuously update device fingerprints.

????Real-World Application:

Improved security policies(Only authorized devices can access the network).

QoS and network optimizationbased on device type.

Dynamic access controlbased on OS and manufacturer.

✅Reference:Huawei HCIE-Datacom Guide – AI-Driven Campus Networks with iMaster NCE

Comprehensive and Detailed In-Depth Explanation:

Analyzing the output:

A. Key authentication is disabled for the tunnel:Correct. The output explicitly states"key disabled".

B. The destination IP address of the tunnel is 10.0.3.3:Correct. The output shows"destination 10.0.3.3".

C. The tunnel is a GRE tunnel:Correct. The output states"Tunnel protocol/transport GRE/IP".

D. Keepalive detection is enabled on the tunnel:Incorrect.The output clearly shows"keepalive disabled".

Therefore, the correct answer isDbecause the tunnel doesnot have keepalive enabled.

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).

Comprehensive and Detailed In-Depth Explanation:

The regular expression100.$can be broken down as follows:

100:Matches the exact sequence of digits "100".

(dot): Representsany single character.

$:Indicates theend of the line.

Therefore, the pattern100.$matches anyfour-character sequencethat starts with "100" and ends withany single character.

1000 (A): Matches because it has four digits, starting with "100" and ending with "0".

1001 (B): Matches because it has four digits, starting with "100" and ending with "1".

10000 (C): Doesnot matchbecause it hasfive digits.

100 (D): Doesnot matchbecause it only hasthree digits.

Huawei’suser access authentication configurationincludes the following components:

AAA scheme: Defines how users are authenticated (local, RADIUS, HWTACACS, etc.).

Domain: Groups users and associates them with an AAA scheme.

Access profile: Defines access control rules like 802.1X, MAC, Portal, or multi-mode authentication.

Correct workflow:

Bind theauthentication profile(which references the access profile) to theuser access interface.

Not the other way around.

Incorrect statement:

D.It incorrectly states youbind the access profile to the authentication profile, when in fact, theauthentication profile binds the access profileand is applied to the interface.

Correct answer: D

Understanding MPLS Forwarding Mechanism

MPLS (Multiprotocol Label Switching) is a high-performance forwarding mechanism that operates on two planes:

1️⃣Control Plane:

EstablishesLabel Switched Paths (LSPs)using protocols likeLDP (Label Distribution Protocol),RSVP-TE (Resource Reservation Protocol - Traffic Engineering), orBGP-LU (BGP Label Unicast).

Assignslabelsto packets based on routing policies.

2️⃣Data Plane (Forwarding Plane):

Uses aLabel Forwarding Information Base (LFIB)instead of traditional IP routing.

Packets areforwarded based on labels, not IP addresses.

Analysis of the Answer Choices

✅C. The system automatically assigns an ID to the upper-layer application that uses a tunnel. This ID is also called the tunnel ID.

Correct:MPLS assigns aTunnel IDto applications that utilize tunnels (e.g.,VPNs, MPLS-TE, or L2/L3 services).

This ID helpsdifferentiate between various tunnel applications, ensuring traffic follows the correct LSP.

❌A. After an IP packet enters an MPLS domain, the MPLS device forwards the packet based on FIB table queries.

Incorrect:MPLS routersdo NOT use the FIB (Forwarding Information Base)for forwarding once labels are assigned.

Instead, they useLFIB (Label Forwarding Information Base)to switch packets based on labels.

❌B. If the tunnel ID is 0x0, the MPLS forwarding process starts.

Incorrect:If theTunnel ID is 0x0, MPLSdoes NOT start; it means no label is assigned, and traditionalIP forwardingoccurs.

❌D. If the tunnel ID is not 0x0, the normal IP forwarding process starts.

Incorrect:If the Tunnel ID isnot0x0, MPLSforwards traffic using label switching, not IP forwarding.

In OSPF-based SR-MPLS TE, Adjacency Segment Identifiers (Adj-SIDs) are locally assigned by each router for its directly connected interfaces. These labels are allocated from the Segment Routing Local Block (SRLB) configured on the router. By default, Huawei routers use an SRLB range starting at 9000, and Adj-SIDs are assigned sequentially (e.g., 9000, 9001, 9002, etc.) to each adjacency.

For P3, adjacency labels correspond to its outgoing interfaces. Assuming P3 has two adjacencies (e.g., to P2 and P4, as inferred from typical network topologies), it will allocate two unique Adj-SIDs from its SRLB. Based on Huawei’s implementation:

The first adjacency (e.g., to P2) is assigned the next available label in the SRLB (e.g., 9002).

The second adjacency (e.g., to P4) is assigned the subsequent label (e.g., 9003).

Analysis of Options:

Option B (9002): Likely assigned to P3’s first adjacency (e.g., link to P2).

Option C (9003): Likely assigned to P3’s second adjacency (e.g., link to P4).

Option A (9006) and D (9005): These labels are likely allocated by other routers (e.g., P4 or P5), as they fall outside the sequential range assigned by P3.

Key Points:

Adj-SIDs are local to the router and do not conflict with labels from other nodes.

The sequential allocation depends on the SRLB configuration. If the SRLB starts at 9000, labels 9000 and 9001 may be reserved for other purposes (e.g., node SIDs or reserved blocks), leaving 9002 and 9003 for adjacency labels.

Conclusion: P3 allocates 9002 and 9003 for its two adjacencies. Thus, B and C are correct.

Comprehensive and Detailed In-Depth Explanation:

Prefix Segment:

Represents adestination prefixin the network.

APrefix SID (Segment Identifier)is a globally unique SID that maps to anIP prefixand is within theSRGB (Segment Routing Global Block)range.

Therefore,Cis correct.

Ais incorrect because a prefix SIDis within the SRGB range, not out of it.

Adjacency Segment:

Represents alink (adjacency)between two nodes.

AnAdjacency SIDislocally significantand typically allocated from theSRLB (Segment Routing Local Block)range.

It uniquely identifies a link between nodes in thesource node’s local routing table.

Therefore,Dis correct, whileBis incorrect because an adjacency SID is not necessarily an offset within the SRGB.

Comprehensive and Detailed Explanation:

✔MPLS labels in SR-MPLS are calculated using the SRGB (Segment Routing Global Block) baseand thePrefix-SID.

✔Label Calculation Formula:

MPLS Label=SRGB Base+Prefix-SID\text{MPLS Label} = \text{SRGB Base} + \text{Prefix-SID}MPLS Label=SRGB Base+Prefix-SID

✔Extracting Values from the LSDB:

SRGB Base:36000

Prefix-SID:300

✔Valid MPLS Labels:

36000 + 300 = 36300

40002 and 38002 fall within the SRGB range.

39002 is outside the expected range, making it theincorrect answer.

????Reference:Huawei HCIE Datacom – Segment Routing Label Calculation

Understanding Huawei SD-WAN VN (Virtual Network) Topologies

Huawei SD-WANusesVirtual Networks (VNs)to providetraffic isolation and policy-based routingfor different services, branches, and applications.

????VN Topologies Can Be Different

Each VN (Virtual Network) can have its own topology.

Some VNs may usefull-mesh, while others may usehub-and-spokeorstar topology.

Different VNs can havedifferent routing and security policies.

✅Example:

Corporate traffic (VN1)→Full-mesh topologyfor efficient inter-branch communication.

Guest Wi-Fi traffic (VN2)→Hub-and-spoke topologyto restrict inter-site communication.

Why is the Answer FALSE?

❌All VNs do not have to use the same topology.

✅Each VN can be configured independently with a unique topology, routing policy, and security settings.

✅Reference:Huawei HCIE-Datacom Guide – SD-WAN VN Topologies and Segmentation

Comprehensive and Detailed In-Depth Explanation:

AnHTTP responsefrom the server to the client typically includes the following components:

Protocol version (C):Specifies the HTTP version used (e.g., HTTP/1.1).

Status code (B):Indicates the response result (e.g., 200 for OK, 404 for Not Found).

Reason phrase (A):A textual description associated with the status code (e.g., "OK", "Not Found").

Headers and Body:Contain additional information and the actual response content.

URI (D):TheUniform Resource Identifieris part of theHTTP requestand not theHTTP response. Therefore,Dis the correct answer.

Comprehensive and Detailed In-Depth Explanation:

In BGP EVPN,Type 2routes (MAC/IP Advertisement routes) are used to advertise:

MAC addressesof endpoints.

ARP entries(MAC-to-IP bindings).

IRB (Integrated Routing and Bridging) routes, allowing the advertisement of both Layer 2 and Layer 3 reachability.

These routes are essential for enabling dynamic VXLAN tunnel establishment and seamless host mobility.

Type 1 (Ethernet Auto-Discovery):Used for multi-homing information.

Type 3 (Inclusive Multicast Ethernet Tag):Used for BUM (Broadcast, Unknown unicast, and Multicast) traffic.

Type 4 (Ethernet Segment):Used for identifying Ethernet segments in multi-homing scenarios.

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

IPsec (Internet Protocol Security) provides secure communication over IP networks by implementing multiple security functions.

✔Data Origin Authentication:

Ensures that the sender of the data is genuine and not impersonated.

Uses techniques such as HMAC (Hash-Based Message Authentication Code).

Correct Match:"The receiver verifies the identity of the sender."✅

✔Data Encryption:

Protects data confidentiality by encrypting packets using AES, 3DES, or other encryption algorithms.

Ensures that only the intended recipient can decrypt the data.

Correct Match:"The sender encrypts the data, and the receiver decrypts the data."✅

✔Data Integrity:

Ensures that data is not altered in transit.

Uses cryptographic hashes (e.g., SHA-256) to verify integrity.

Correct Match:"The receiver verifies received data to determine whether the data has been tampered with."✅

✔Anti-Replay:

Protects against packet replay attacks, where an attacker resends captured packets to disrupt communication.

Uses sequence numbers to detect and reject duplicate packets.

Correct Match:"The receiver rejects duplicate data packets."✅

????Reference:Huawei HCIE Datacom – IPsec Security Functions

Understanding Network Monitoring Data Categories

????Network devices operate across three functional planes:

✅A. Management Plane:

Handlesdevice configuration, authentication, and monitoring.

Example:SNMP, SSH, NETCONF logs.

✅B. Data Plane (Forwarding Plane):

Handlespacket forwarding and switching.

Example:Interface statistics, traffic rates, dropped packets.

✅C. Control Plane:

Handlesrouting, signaling, and protocol operations.

Example:BGP, OSPF, and MPLS signaling messages.

❌D. Monitoring Plane (Incorrect Choice):

There is no "monitoring plane" in network architecture.

Monitoring tools collect data frommanagement, control, and data planes, butdo not form a separate plane.

Why is the Answer D (Monitoring-plane data)?

❌Monitoring-plane does not exist as a separate category in network architecture.

✅O&M tools collect data from management, control, and data planes, but do not define a separate "monitoring plane".

Real-World Application:

Huawei iMaster NCE-Campus & iMaster NCE-WANcollect real-timenetwork statistics and alarms.

Network Performance Monitoring (NPM)toolsanalyze control-plane eventsto detect failures.

✅Reference:Huawei HCIE-Datacom Guide – Network Planes and Performance Monitoring

Link-LSA (Type 8)in OSPFv3 performs the following:

Advertises therouter’s link-local addressto neighbors.

Advertises therouter’s interface IDon the link.

CarriesIPv6 prefixesassociated with the interface (since Router LSA no longer does this in OSPFv3).

TheOptions field in Link-LSAcontainscapabilities of the originating router,notthe options from Network-LSA.

So,Option D is incorrect— the Link-LSA doesnot advertise options from the Network-LSA.

Correct answer: D

Understanding Inter-AS MPLS L3VPN Option C

????MPLS L3VPN provides Layer 3 VPN services over an MPLS backboneby using BGP to exchange VPN routes.

????Inter-AS MPLS L3VPN Option C (Carrier-to-Carrier Model) works as follows:

ASBRs (Autonomous System Boundary Routers) exchangeVPNv4 routes using MP-BGP.

ASBRsdo NOT store VPN routing tables. Instead, theyadvertise labeled IPv4 routesto enable inter-AS forwarding.

How ASBR-PE2 Enables Inter-AS Communication?

✅VPNv4 Address Family (Answer A - Required)

Used to exchangeMPLS VPN routes between PE routers.

MP-BGP (Multiprotocol BGP) exchanges VPNv4 prefixesbetween ASBR-PE1 and ASBR-PE2.

✅Unicast BGP Address Family (Answer D - Required)

Required to exchangeIPv4 labeled routesbetween ASBRs.

EnsuresMPLS label forwarding between AS100 and AS200.

❌BGP-LS Address Family (Answer B - Not Required)

BGP-LS (BGP Link-State) is used for SDN controllersto learn topology information.

It isnot required for Inter-AS MPLS L3VPN.

❌VPN Instance Unicast Address Family (Answer C - Not Required)

This is used forPE-CE communicationbut isnot required between ASBRs.

Why is the Answer A, D?

✅VPNv4 routes enable inter-AS VPN communication.

✅IPv4 unicast routes are required for ASBR-PE2 to forward packets across AS boundaries.

Real-World Application:

Service Provider Networks:Used incarrier-to-carrier MPLS VPN deployments.

Enterprise WAN Interconnection:Enablesmulti-AS MPLS VPN connectivityfor large enterprises.

✅Reference:Huawei HCIE-Datacom Guide – Inter-AS MPLS L3VPN Option C (Carrier-to-Carrier Model)

Comprehensive and Detailed Explanation:

R2 is anArea Border Router (ABR), meaning itconnects multiple OSPF areas(Area 0 and Area 1).

ABRs generate Router-LSAs for each area they belong to.

SinceR2 is part of both Area 0 and Area 1, it must generateRouter-LSAs (Type 1) for both areas.

R2 does not forward Router-LSAs between areas; instead, it generatesSummary LSAs (Type 3)to exchange routing information between areas.

Thus, the correct answer isD.

????Reference:Huawei HCIE Datacom – OSPF LSA Types and ABR Behavior

NETCONF definesdatastoresto manage device configurations:

running: Active configuration in use

candidate: Staging area for changes before applying

startup: Configuration loaded on reboot

NETCONF operations:

: Applies changes fromcandidate → running→✅

: Deletes a specified datastore (e.g., startup) →✅

: Validates syntax/logic in thecandidate datastore→✅

Statement D is incorrect: never submits config from startup to running— that’s handled automatically at boot time, not through NETCONF commands.

Correct answer: D

OSPF (Open Shortest Path First) Router-LSA (Type 1 LSA)describesall directly connected OSPF linksof a router and their types. Thefollowing link types can appear in a Router-LSA:

Point-to-Point (P-2-P) (B)– Represents adirect connection between two routers.

Virtual Link (Vlink) (C)– Used toconnect an area to the backbone (Area 0)when a direct connection is unavailable.

Stub Network (StubNet) (D)– Represents anetwork with only one exit point(e.g., a loopback interface or passive interface).

Incorrect Option:

TransNet (A) – Incorrect!

Transit networks appear in Network LSAs (Type 2), not Router LSAs.

Reference from Huawei HCIE-Datacom Documentation:

Huawei OSPF Configuration Guide – Router-LSAs and Link Types

HCIE-Datacom Training Material – OSPF LSAs and Topology Advertisement

Comprehensive and Detailed Explanation:

Inter-AS MPLS L3VPN solutions enable communication between differentAutonomous Systems (AS)while maintaining VPN separation. The three primary solutions for inter-AS MPLS L3VPN are:

Option A (Back-to-Back VRF)

MPLS isnot requiredbetween ASBRs.

VPN routes are exchangedwithout label switching.

Each ASBR has aVRF instanceconfigured and forwards traffic usingplain IP routing.

Option B (eBGP Redistribution of Labeled VPNv4 Routes)

MPLSis not requiredbetween ASBRs.

ASBRsexchange labeled VPNv4 routes using eBGP.

The ASBR doesnot perform label switchingbut simply forwards packets based on VPNv4 labels.

Option C (Multi-Hop MP-BGP for VPNv4 Routes)

MPLS is requiredbetween ASBRs.

ASBRs establishlabel-switched paths (LSPs)to forward VPN traffic across AS boundaries.

SinceOption Brelies onlabeled VPNv4 routes via eBGPand does not need MPLS between ASBRs, the correct answer isD.

????Reference:Huawei HCIE Datacom Study Guide - MPLS VPN Inter-AS Solutions

✔Egress devicesinHuawei CloudCampus static IPsec VPNinclude:

Access Points (APs)

Routers

Firewalls✅

✔Why Firewalls?

Firewallssupport IPsec VPN terminationforsecure WAN interconnection.

Firewalls provideadvanced security filteringandencryptionfor IPsec traffic.

????Reference:Huawei HCIE Datacom – IPsec VPN in CloudCampus

SSH Public Key Authentication

Inpublic key authentication mode, the SSH client must generate akey pair (public and private keys)before connecting to an SSH server.

✅C. ssh-keygen -t dsa (Correct Answer)

DSA (Digital Signature Algorithm) key generationfor SSH authentication.

Generates aprivate key (id_dsa)and apublic key (id_dsa.pub).

IS-IS was originally designed for IPv4, but extensions via TLVs (Type-Length-Value) allow it to support IPv6. These are referred to as New IS-IS TLVs, including TLV 236 (IPv6 Reachability), TLV 232 (IPv6 Interface Address), etc. These TLVs are crucial for IPv6 route computation within IS-IS.

Exact Extract - HCIE-Datacom Guide – IPv6 Routing Protocols Chapter

“IS-IS uses new TLVs such as TLV 236 and TLV 232 to carry IPv6 prefix and interface address information. These TLVs are essential to enable IPv6 route calculation.”

Understanding VXLAN and NVE Interfaces

VXLAN (Virtual Extensible LAN)allows forLayer 2 network extensionoverLayer 3 infrastructure.

????Key VXLAN Components:

NVE (Network Virtualization Edge) Interface→ VXLAN tunnels are created usingone or more NVE interfaces.

BD (Bridge Domain)→ Logical grouping of VXLAN traffic.

VNI (VXLAN Network Identifier)→ 24-bit unique ID for traffic segmentation.

????Analysis of Each Option:

✅A. One NVE interface can be used for multiple VXLAN tunnels if ingress replication is used.

Correct:VXLAN tunnels can be dynamically learned usingBGP EVPN, meaning multiple tunnels can use the sameNVE interface.

✅B. An NVE interface can be associated with multiple VNIs, allowing multiple BDs on one NVE.

Correct:Each NVE interface can carrymultiple VNIs, reducing the need for separate interfaces.

❌C. One NVE interface must be created per VXLAN tunnel.

Incorrect:Multiple VXLAN tunnelscan share a single NVE interface.

❌D. One NVE must be created for each BD.

Incorrect:One NVE can support multiple BDs.

????Real-World Application:

Cloud Data Centers:VXLAN enablesmulti-tenant network segmentation.

Campus Networks:SimplifiesLayer 2/Layer 3 connectivityacross sites.

✅Reference:Huawei HCIE-Datacom Guide – VXLAN and NVE Configuration

Comprehensive and Detailed Explanation:

✔Hub-Spoke networkingis the mostefficient and scalablemodel for interconnecting100+ branchesin asmall and midsize campus network.

✔Why Hub-Spoke?

Centralized Control:Ahub routermanages communication betweenspoke routers(branch sites).

Reduced Complexity:Unlikefull-mesh, which requiresN(N-1)/2* connections,hub-spoke minimizes link costs.

Easier Management:Policy enforcement and security are centralized at thehub site.

✔Why Not Other Options?

❌A (Direct Networking)→ Suitable forsmall networks, but inefficient for100+ branches.

❌B (Full-Mesh Networking)→ Highcost and complexity, requiringtoo many links.

❌D (Partial-Mesh Networking)→ More scalable thanfull-mesh, buthub-spoke is more optimizedfor large branch networks.

????Reference:Huawei HCIE Datacom – WAN Interconnection Models

Comprehensive and Detailed Explanation:

✔gRPC supports four types of RPCs:

Unary RPC→ Client sendsonerequest, server respondsonce.

Server streaming RPC→ Server sendsmultiple responses.

Client streaming RPC→ Client sendsmultiple requests.

Bidirectional streaming RPC→Bothsides exchange multiple messages.

✔Why B and C Are Incorrect:

❌(B) Incorrect→ The method rpc dataPublish(stream serviceArgs) returns(stream serviceArgs) {} violates gRPC syntax.

❌(C) Incorrect→ rpc stream LotsOfGreetings(HelloRequest) returns (HelloResponse) {} containsincorrect stream positioning.

????Reference:Huawei HCIE Datacom – gRPC API and Streaming Mechanisms

Comprehensive and Detailed Explanation:

On-premise moderefers to deploying theHuawei iMaster NCE-Campus controllerwithin the enterprise network instead of using a cloud-based solution.

✔Best suited forsmall and midsize campus networksthat require:

Greater control over data security

Local network automation

No reliance on cloud connectivity

Sinceon-premise mode is recommended for small and midsize campus networks, the statement isTRUE.

????Reference:Huawei HCIE Datacom – iMaster NCE Deployment Modes

Virtual Networks in Huawei CloudCampus Solution:

Virtual networks (VNs) aresegmented based on services(e.g., IoT, Guest Wi-Fi, Enterprise Wi-Fi).

Each VN has its ownrouting and forwarding instance(VRF).

Isolation Between Virtual Networks:

By default,different virtual networks are isolated.

If inter-VN communication is required, it must be manually configuredusingpolicy-based routing (PBR), inter-VRF routing, or firewall policies.

Reference from Huawei HCIE-Datacom Documentation:

Huawei CloudCampus Solution Guide – Virtual Networks and Segmentation

HCIE-Datacom Training Material – Policy-Based Inter-VN Communication

Network migration typically includes the followingphases:

Preparation Phase:

Network survey

Migration plan design

Backup

Pre-configuration

Middle Phase (Migration Execution):

On-site monitoring

Migration implementation

Service test (to verify the migration effect)

Post-Migration Phase:

Optimization

Documentation

Final acceptance

Hence,Migration preparationis part of theinitial phase, not themiddle phase.

Correct answer: A. Migration preparation

Infirewall hot standby (HRP - Hot Standby Routing Protocol) mode, certain data can be synchronized between the active and standby firewalls to ensure uninterrupted service.

Thefollowing data is backed up:

✅Server mapping table:Contains information about NAT mappings and other session mappings.

✅AAA user table (excluding the default user admin):Ensures that authenticated users do not need to re-authenticate in case of failover.

✅Session table:Ensures that existing connections remain active when switching to the standby firewall.

❌Dynamic MAC address table is NOT backed upbecause it is dynamically learned and not relevant to firewall session synchronization.

✅Reference:Huawei HCIE-Datacom Guide - Firewall HRP Synchronization

Understanding EVPN (Ethernet VPN) and ARP Request Handling

????What is EVPN?

EVPN (Ethernet VPN) is aBGP-based control plane for VXLANthat improvesLayer 2 & Layer 3 network scalability.

Eliminatesflood-and-learn behaviorusingBGP MAC/IP advertisement routes.

????Why is an ARP Request Sent?

WhenCE1 (192.168.1.1/24) wants to communicate with CE2 (192.168.1.2/24), it sends anARP requestto discover the MAC address of CE2.

????How Does EVPN Process the ARP Request?

1️⃣PE1 receives the ARP request from CE1.

2️⃣PE1 sends a MAC/IP advertisement route (Type 2 EVPN route) to inform PE2 and PE3 of CE1’s MAC address.

3️⃣PE1 forwards the ARP request as BUM (Broadcast, Unknown unicast, and Multicast) traffic to PE2 and PE3.

4️⃣PE3 (Designated Forwarder - DF) forwards the packet to CE2.

5️⃣PE2 (Non-DF) does NOT forward the packet to avoid loops.

Analysis of the Answer Choices:

✅A. When forwarding the packet to PE3, PE1 needs to add the BUM traffic label allocated by PE3 to the packet.

Correct:

BUM (Broadcast, Unknown Unicast, Multicast) traffic in EVPNis encapsulated with aspecial labelassigned by the receiving PE.

PE1adds the BUM traffic label for PE3before sending the ARP request.

✅B. PE1 sends a MAC/IP advertisement route carrying the MAC address of CE1.

Correct:

EVPN Type 2 MAC/IP advertisement routesare sent to inform other PEs of CE1’s MAC/IP binding.

❌C. PE2 forwards the packet to CE1.

Incorrect:

PE2 is the Non-Designated Forwarder (Non-DF)anddoes NOT forward BUM trafficto avoid loops.

✅D. PE3 forwards the packet to CE1.

Correct:

PE3 is the Designated Forwarder (DF) for this segment, meaning itforwards the ARP request to CE2.

Final Answer: A, B, D

✅Reference:Huawei HCIE-Datacom Guide – EVPN BGP MAC/IP Advertisement and BUM Traffic Handling

Real-World Application:

Data Center Interconnect (DCI):EVPN prevents excessiveARP floodingacross VXLAN networks.

Enterprise Campus Networks:UsesEVPN VXLAN to scale Layer 2 connectivity across multiple locations.

Option B is incorrect because it falsely states that EBGP cannot be configured on Spoke-PE or Spoke-CE if the Hub-CE and Hub-PE run IGP. In reality, EBGP can still be used between Spoke sites and PE devices, regardless of the protocol between the Hub PE and CE. EBGP is often used for PE-CE communication, including in Hub-and-Spoke architectures.

Exact Extract - Huawei HCIE-Datacom VPN Section:

“In Hub&Spoke deployments, EBGP can be deployed between Spoke-CE and Spoke-PE. The choice of routing protocol between Hub-CE and Hub-PE does not limit this.”

InSR-MPLS (Segment Routing over MPLS),prefix SID conflictsmay occur if multiple prefixes are assigned the same SID or vice versa.

Conflict resolution principle (Huawei standard):

When there aremultiple SIDs for the same prefix, theSID with the lowest value wins.

Whenthe same SID is assigned to multiple prefixes, theprefix with the smallest addresswins.

Apply to this case:

Conflict: Two entries for1.1.1.1/32withSID 2 and SID 1.

SID 1 is lower, so1.1.1.1/32 → SID 1is selected.

Correct answer: D. 1.1.1.1/32 → SID 1

Segment Routing over IPv6 (SRv6) defines several headend behaviors for how SRH (Segment Routing Headers) are added:

B. H.Insert — Inserts an SRH into an existing IPv6 packet.

C. H.Encaps — Encapsulates the original packet in a new IPv6 packet with an SRH.

D. H.Insert.Red — Performs insert behavior and reduces the payload for optimization.

A. H.Encaps.Red is not a defined SRv6 behavior — it’s an invalid option.

Exact Extract - Huawei SRv6 White Paper:

“H.Insert, H.Insert.Red, and H.Encaps are valid behaviors for injecting SRH. H.Encaps.Red is not defined in the SRv6 headend behavior set.”

Understanding OSPF Multi-Area Routing

????OSPF (Open Shortest Path First) is a link-state routing protocolthat uses ahierarchical area designfor scalability.

????OSPF Areas in the Diagram:

Area 0 (Backbone Area):ContainsR4 (Loopback 10.0.4.4/32).

Area 1:ContainsR1 (Loopback 10.0.1.1/32) and R2 (Loopback 10.0.2.2/32).

Area 2:ContainsR3 (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 inArea 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, soR2 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 toscale large enterprise networkswhile maintainingfast convergence.

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

HuaweiSD-WAN establishes secure tunnels between SD-WAN edge devices (CPEs, AR routers, and controllers) using tunneling protocols.

✅B. GRE over IPsec(Correct Answer)

GRE (Generic Routing Encapsulation) over IPsecisthe primary tunneling method used in Huawei SD-WAN.

GRE provides multi-protocol encapsulation, whileIPsec ensures encryption and security.

Used forsecure communication over public WAN links (e.g., the internet, LTE, MPLS, etc.).

Comprehensive and Detailed Explanation:

Thereset isis allcommand resets theentire IS-IS process, including:

✔Neighbor adjacencies

✔LSDB (Link-State Database)

✔All IS-IS-related statistics

Key Points:

This commandresets IS-IS completely, causingtemporary route convergence delays.

All IS-IS statistics are clearedbecause the process restarts from scratch.

Since the question states thatIS-IS statistics are not cleared, which is incorrect, the correct answer isFALSE.

????Reference:Huawei HCIE Datacom – IS-IS Troubleshooting and Reset Commands

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

InOSPFv3, each LSA type has adefined flooding scope:

Link-LSA (Type 8)

Advertisedonly on the local link

Contains router’s link-local address and prefixes

Scope:Within the local link scope✅

AS-External-LSA (Type 5)

Used to advertiseexternal routes from outside the AS

Flooded across theentire autonomous system, except stub/NSSA areas

Scope:Within an AS✅

Network-LSA (Type 2)

Generated by theDesignated Router (DR)

Describes all routers on a broadcast or NBMA segment

Floodedwithin the originating area

Scope:Within an area✅

Correct Mappings:

Link LSA→Within the local link scope

AS-External-LSA→Within an AS

Network-LSA→Within an area

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

IPsec (Internet Protocol Security) provides secure communication over IP networks through several essential functions. Let’s explain each function and its purpose:

1. Data Origin Authentication:

Description:The receiver verifies the identity of the sender.

This function ensures that the data received actually comes from the claimed source.

IPsec achieves this usingIKE (Internet Key Exchange)anddigital signatures.

TheAuthentication Header (AH)andEncapsulating Security Payload (ESP)support authentication.

Use Case:Verifying that a message claiming to be from a specific IP address is genuinely from that source.

2. Data Encryption:

Description:The sender encrypts the data, and the receiver decrypts the data.

Encryption ensuresdata confidentialityby transforming readable data (plaintext) into unreadable data (ciphertext).

Only the intended receiver with the correct decryption key can convert the ciphertext back to plaintext.

Common encryption algorithms used includeAES (Advanced Encryption Standard)andDES (Data Encryption Standard).

Use Case:Protecting sensitive data transferred over public networks.

3. Data Integrity:

Description:The receiver verifies received data to determine whether the data has been tampered with.

Ensures that the data was not altered during transmission.

Uses cryptographichash functions(e.g.,SHA-1, SHA-256) to generate amessage digest.

The digest is sent with the data and verified on the receiving side.

Use Case:Detecting any changes made to the data packet during transmission.

4. Anti-Replay:

Description:The receiver rejects duplicate data packets.

Prevents attackers from capturing packets and replaying them later.

Usessequence numbersto detect replayed or duplicated packets.

The receiver keeps asliding windowof sequence numbers to compare incoming packets.

Use Case:Blocking malicious actors from sending previously intercepted packets to disrupt communication.

Why This Mapping Is Correct:

The functions and descriptions are aligned based on the core concepts of IPsec and the roles they play in ensuring secure data transmission.

Each function addresses a specific aspect of security:authentication, confidentiality, integrity, and replay protection.

In MPLS LDP, there are two types of sessions:

Direct LDP sessions: Established between directly connected LSRs using LDP Hellos over a link.

Remote LDP sessions (also called targeted LDP sessions): Established between non-directly connected LSRs. These requiremanual configurationof the remote peer.

In this scenario, SWA and SWC arenot directly connected, so aremote (targeted) LDP sessionmust be set up.

For a remote LDP session:

Youmust configure the remote peerusing the command:

[SWA-MPLS-LDP] targeted-peer x.x.x.x

Where x.x.x.x is theLSR ID of SWC(33.3.3.3 in this case).

The current configuration does not include this required step.

Thus, the correct statement is:

D. You need to create a remote peer and specify an LSR ID for the remote peer.

Comprehensive and Detailed Explanation:

✔SRv6 Locator and Segment Structure:

TheSRv6 Locatoris2001:DB8:ABCD::/64→ This defines the segment routing namespace for this node.✅

Dynamic Segment (SID)=32 bits→ Defined dynamically per segment.✅

Args Field=32 bits→ Used for function arguments.✅

❌(B) Incorrect→Static segments are NOT explicitly defined as 32-bit fieldsin Huawei SRv6.

????Reference:Huawei HCIE Datacom – SRv6 Locator and SID Structure

Comprehensive and Detailed In-Depth Explanation:

In the Label Distribution Protocol (LDP) session establishment process, theInitialization messageis sent by the initiator to propose parameters for the session. If the responder finds that the proposed parameters are not acceptable, it responds with anError Notification Message. This message indicates that the session could not be established due to incompatible or incorrect parameters.

TheError Notification Messagetypically includes details about why the session could not be established, such as parameter mismatch or unsupported features. If the parameters are acceptable, the responder would instead reply with aKeepalive Messageto maintain the session.

Understanding Route Reflectors (RRs) in Huawei SD-WAN

In Huawei’sSD-WAN Solution, BGPRoute Reflectors (RRs)are used toreduce the number of BGP peer relationshipsand optimize routing scalability.

????Key Functions of an RR in SD-WAN:

CentralizesBGP route distributionin large-scale SD-WAN networks.

Reducesfull-mesh BGP peering complexity.

Improves network scalabilityand convergence time.

Analysis of Each Deployment Mode:

✅B. Independent deployment of the RR

Correct:The RR is deployed as astandalonedevice, independent of the SD-WAN hub site.

Best for large-scale SD-WAN deploymentsrequiring dedicated route control.

✅C. Co-deployment of the RR and hub site

Correct:The RR is co-located with the SD-WANhub site, reducing infrastructure overhead.

Best for mid-sized SD-WAN deploymentswhere thehub and RR functions can be combined.

✅D. Partially independent deployment of the RR

Correct:The RR ispartially separatedfrom the hub but still shares some resources.

Provides a balance between full independence and co-location.

❌A. Multi-area deployment of the RR (Incorrect Choice)

Multi-area RR deployment isnot a common Huawei SD-WAN practice.

Huaweidoes not require separate RRs per area, as SD-WAN is based oncentralized policy-based routing.

Real-World Application:

Large Enterprise SD-WAN:Usesindependent RRsto optimizeglobal network routing.

Service Provider SD-WAN:Usesco-deployed RRsto reduce infrastructure costs while maintainingroute scalability.

✅Reference:Huawei HCIE-Datacom Guide – BGP Route Reflectors in SD-WAN Architecture

In Huawei’sCloudCampus Solution, VNs (Virtual Networks) areisolated by defaultfor security purposes. To enableinter-VN communication, you must explicitly configure policies that allow traffic between different VNs.

The correct way to control and enable this communication is viarouting policies, especiallyinter-VN routing policieson thecore or border nodes.

Static routesorOSPF deploymentsare not sufficient or appropriate for policy-controlled VN communication in this context.

Correct answer: D. Deploy a routing policy

The provided Python code uses the requests.post() function to make an HTTP POST request to retrieve a token from iMaster NCE. The body is structured using the json={} parameter, which serializes the dictionary into JSON format. The proper content-type and accept headers are included.

Let's analyze each option:

✅ Option A is correct: The print(r.json()) is a valid method to display JSON response from the server.

✅ Option B is correct: The token URL is constructed correctly: https://139.9.213.72:18002/controller/v2/tokens.

✅ Option C is correct: The request body is clearly in JSON format, specified by the json={...} argument.

❌ Option D is incorrect: The HTTP method used is POST, not GET. The statement is false, making it the correct answer to select.

Huawei Official Documentation Reference:

“To obtain a token, the client sends a POST request to /controller/v2/tokens, including credentials in the request body in JSON format.”

(Source: Huawei iMaster NCE RESTful API Reference Guide – Authentication Section)

Huawei IPsec supports multiple modes for establishing Security Associations (SAs):

A. Template negotiation — Used in IPsec policy templates and dynamic VPNs.

B. IKE auto-negotiation mode — Automatically negotiates parameters via IKE Phase 1/2.

C. Certificate negotiation — IPsec peers can authenticate each other using certificates during IKE negotiation.

D. Manual mode — Static IPsec SAs can be manually configured without IKE, often used in simple or static topologies.

Exact Extract - Huawei Security Configuration Guide (USG Series):

“IPsec SAs can be established manually or dynamically through IKE, including using PSKs or certificates. Template-based approaches simplify large-scale deployment.”

Comprehensive and Detailed Explanation:

✔Breakdown of the Python Code:

✅(A) Correct→ The function r.json() can be used to display theserver response (token details).

✅(B) Correct→ Thetoken request URLis correct.

✅(D) Correct→ The request body is inJSON format(json={"userName": nbi_name, "password": nbi_pwd"}).

❌(C) Incorrect→ The requestuses POST, not GET(requests.post() is explicitly called).

????Reference:Huawei HCIE Datacom – iMaster NCE RESTful API Authentication

Huawei iMaster NCE-CampusWi-Fi Location-Based Services (LBS)useHTTP/HTTPSto send location data (such as AP association, signal strength, timestamp, etc.) to an externalLBS platform.

Thestandard format for such data exchange is JSON (JavaScript Object Notation).

JSON is lightweight, readable, and widely supported by modern web APIs and platforms.

Other options:

XML: Used in legacy systems, heavier format.

HTML: Used for page rendering, not data transfer.

YAML: Used mainly in configurations, not standard for HTTP APIs.

Correct answer: C. JSON

Understanding User Authentication Points in a Network

Authentication pointscan be deployed at different network layersbased on security and scalability needs:

✅Access Layer Authentication:

Ensureshigh security & granular control(user-level authentication).

Preferred inhigh-security enterprise networks.

✅Aggregation or Core Layer Authentication:

Reduces authentication overheadbutprovides less granular control.

Suitable forlarge-scale networkswhere authentication load needs to be balanced.

Analysis of the Answer Choices:

✅A. Deploying user authentication points at the access layer achieves granular permission management and high network security.

Correct:Providesfine-grained control per userand prevents unauthorized access.

✅B. Moving user authentication points from the access layer to the aggregation or core layer greatly reduces the number of user authentication points, thereby effectively mitigating the pressure on the AAA server.

Correct:Fewer authentication points meanless load on the AAA server.

✅C. Deploying user authentication points at the access layer has both advantages and disadvantages when compared to doing so at the aggregation or core layer. Policy association can be applied if user authentication points are deployed at the access layer.

Correct:Policy-based authentication isbest applied at the access layerforgranular control.

❌D. When user authentication points are moved from the access layer to the aggregation layer, MAC address authentication for users may fail.

Incorrect:MAC authentication worksat both layers, butpolicy adjustmentsmay be needed.

✅Reference:Huawei HCIE-Datacom Guide – User Authentication Strategies in Enterprise Networks

BGP EVPN in VXLAN Tunneling

✅A. MP_REACH_NLRI is used to carry routing information.

MP_REACH_NLRI (Multiprotocol Reachable Network Layer Reachability Information)is used inBGP updatesto carryVXLAN reachability information.

✅B. Several BGP EVPN routes are defined through BGP extension.

BGP EVPN introduces multiple route types, such asType 2 (MAC/IP Advertisement), Type 3 (Inclusive Multicast), and Type 5 (IP Prefix Advertisement).

✅D. MP_REACH_NLRI is used to carry the RT.

RT (Route Target) defines route import/export policies in VPN environments.

MP_REACH_NLRI carries the RT attributein BGP EVPN updates.

❌Incorrect Answer:

❌C. MP_REACH_NLRI is used to carry the RD.

Wrong!TheRoute Distinguisher (RD)is carriedinside BGP attributes, but not in MP_REACH_NLRI.

Reference from Huawei HCIE-Datacom Documentation:

Huawei VXLAN BGP EVPN Configuration Guide – BGP EVPN Route Types

HCIE-Datacom Training Material – VXLAN Dynamic Tunnel Establishment

Comprehensive and Detailed In-Depth Explanation:

In MPLS (Multi-Protocol Label Switching), thelabel retention modedetermines how an LSR (Label Switching Router) handles labels received from its neighbors:

Liberal Mode:

An LSRretains all labels distributed by its neighbors, not just the labels from the next-hop LSR.

This approachensures faster convergencebecause the LSR does not need to request new labels if the next hop changes.

Itdoes not save memory or label space, as it stores more labels than strictly necessary.

Conservative Mode:

An LSRonly retains labels from its next-hop neighbors, saving memory and label space.

StatementsCandDare correct because they accurately describe liberal mode.

StatementsAandBare incorrect because they describe conservative mode.

Understanding Huawei CloudCampus Access Control

Huawei’sCloudCampus solutionprovidescentralized authentication and policy managementviaiMaster NCE-Campus.

????Analysis of Each Option:

✅A. iMaster NCE can function as an authentication server.

Correct:iMaster NCE includesAAA (Authentication, Authorization, and Accounting) capabilities, reducing dependency on external servers.

❌B. Cloud APs support local Portal authentication.

Incorrect:HuaweiCloud APs do NOT support local Portal authentication.

Instead,Portal authentication is managed centrally by iMaster NCE, NOT by individual APs.

✅C. iMaster NCE can function as a Portal relay device.

Correct:It can relay authentication requests to aRADIUS or AAA server.

✅D. iMaster NCE can interconnect with a third-party RADIUS server.

Correct:It supports integration withexternal RADIUS authentication serversforenterprise authentication.

Real-World Application:

Used inWi-Fi 6 enterprise deploymentswhere centralizedauthentication, security, and policy enforcementare needed.

✅Reference:Huawei HCIE-Datacom Guide – CloudCampus Authentication Architecture

Understanding SRLB (Segment Routing Local Block)

????What is SRLB?

SRLB (Segment Routing Local Block)is arange of local MPLS labelsused bySegment Routing (SR-MPLS).

These labels areonly relevant to the local routerand arenot advertised to other routers.

????Key SR-MPLS Label Blocks:

✅SRGB (Segment Routing Global Block)– Globally significant labels shared among routers.

✅SRLB (Segment Routing Local Block)– Locally significant labels, not shared.

Why is the Answer TRUE?

✅SRLB labels are only locally defined and are NOT distributed via IGP (OSPF or IS-IS).

✅They are used for local forwarding decisions within an SR-enabled router.

✅Only SRGB labels are advertised to ensure consistent global label assignment.

Real-World Application:

Traffic Engineering (TE):Uses SRLB forcustom local path optimizations.

Segment Routing Networks:Ensuresscalable MPLS forwardingwithout requiring full LDP signaling.

✅Reference:Huawei HCIE-Datacom Guide – Segment Routing Label Blocks (SRGB & SRLB)

Comprehensive and Detailed In-Depth Explanation:

In theCloudCampus public cloud scenario, when devices are deployed through theHuawei registration query center, there isno need to configure DHCP Option 148on the campus network’s DHCP server.

Theregistration query centerautomatically provides thecontroller IP addressto the devices during the registration process.

DHCP Option 148is typically used to provide theiMaster NCE-Campus addressin on-premises or private cloud scenarios.

In thepublic cloud scenario, the devices obtain this information directly from the Huawei cloud platform, makingOption 148 unnecessary.

Comprehensive and Detailed In-Depth Explanation:

BGP4+ (BGP for IPv6) uses theMP_REACH_NLRI(Multiprotocol Reachable Network Layer Reachability Information) attribute to advertise IPv6 routes. This attribute is part of BGP's multiprotocol extensions (RFC 2858), allowing BGP to support multiple address families, including IPv6.

MP_REACH_NLRI:Advertises reachable IPv6 prefixes along with next-hop information.

MP_UNREACH_NLRI:Used to withdraw previously advertised IPv6 routes.

Since IPv6 addresses are significantly different from IPv4 addresses in structure and length (128 bits), the traditional BGP update message format (which supports only IPv4) is insufficient. TheMP_REACH_NLRIattribute solves this by carrying IPv6-specific information.

To automatically enable MPLS on an interface inSR-MPLS:

Segment routing must be enabled globallyin thesystem view→✅

Segment routing must also be enabled under the IGP process, andIGP (OSPF or IS-IS) must be enabled on the interface→✅

Clarifications:

SRGB (Segment Routing Global Block)configuration defines SID ranges butdoes not trigger MPLS enablement→❌

Static adjacency labelsare advanced options and do not auto-enable MPLS →❌

Correct answers: B, D

Understanding OSPF Neighbor States

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

1️⃣Down:No Hello packets received.

2️⃣Init:Routerreceives Hello packetsbutits own Router ID is missingin the received packets.

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

4️⃣ExStart:Routersstart exchanging LSAsbut may faceMTU mismatches.

5️⃣Exchange:Routers sendDatabase Description (DBD) packetsto synchronize link-state databases.

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

7️⃣Full: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 in2-Way statesince 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 butdoes not see its own Router ID, it stays in theInit 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, theDBD exchange fails, causing routers to remain inExStart state.

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

Incorrect:

InAttempt state, routerssend unicast Hello packetsto manually configured neighbors (common inNBMA networks).

If no Hello responses are received, they remain inAttempt state, but theyDO send Hellos.

Real-World Application

OSPF Troubleshooting:Identifying routers stuck inInit or ExStart statescan point toMTU mismatches or neighbor misconfigurations.

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

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

Understanding Telemetry Encoding Formats

????What is Telemetry?

Telemetry is a real-time network monitoring methodthat provideshigh-frequency data collection.

Used inAI-driven networks for predictive analytics and automation.

????Common Telemetry Encoding Formats:

✅GPB (Google Protocol Buffers)

Highly efficient binary formatthat reducesmessage size and CPU overhead.

Commonly used forhigh-speed, real-time analytics.

✅JSON (JavaScript Object Notation)

Human-readable format, widely used inRESTful APIs.

Less efficientthan GPB in high-speed telemetry buteasier to debug.

????Why is the Answer FALSE?

❌GPB is not mandatory; JSON can also be used in telemetry.

✅Huawei supports both GPB and JSON telemetry encoding formats.

Real-World Application:

Cloud Networking:UsesGPB for fast data collectionandJSON for API-based telemetry visualization.

AI-Driven Networks:High-speedAI analyticsleverageGPB encodingfor efficiency.

✅Reference:Huawei HCIE-Datacom Guide – Telemetry Encoding Formats and Data Collection

Understanding Huawei SD-WAN Tunneling Technologies

Huawei SD-WAN usessecure tunnelingto connect branches, data centers, and cloud services.

????Tunneling Technologies in SD-WAN:

✅IPsec (Answer B)→ Providessecure encrypted tunnelsover public or private networks.

✅GRE over IPsec (Answer D)→Encapsulates traffic inside GRE, then encrypts with IPsec, enabling support for multicast and non-IP traffic.

❌A. WLAN (Incorrect Choice)→ WLAN is awireless technology, not a tunneling protocol.

❌C. MPLS (Incorrect Choice)→ MPLS is acore network transporttechnology but is not used to establish SD-WAN data channels directly.

Why are Answers B and D Correct?

✅Huawei SD-WAN primarily uses IPsec for data encryption.

✅GRE over IPsec is used when supporting multicast or dynamic routing protocols over tunnels.

✅Reference:Huawei HCIE-Datacom Guide – SD-WAN Tunneling Mechanisms

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.

Huawei SD-WAN supports various intelligent traffic steering mechanismsto optimize link utilization andbalance network trafficacross multiple links.

✅D. Traffic bandwidth-based traffic steering

This method ensures that traffic isdistributed across multiple links based on available bandwidth.

SD-WAN dynamically selects linksbased on their real-time bandwidth utilization,ensuring optimal performance and load balancing.

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.”

Comparison Between Paramiko (SSH) and Telnetlib (Telnet)

✅Paramiko (SSH) is more secure than Telnetlib (Telnet).

SSH (Secure Shell) encrypts login credentials and session datausing encryption protocols likeAES and RSA.

Telnet transmits data in plaintext, making it vulnerable to eavesdropping and man-in-the-middle attacks.

✅Why is Telnet Insecure?

No encryption→ Credentials (username/password) are sent in plaintext.

Easily interceptedby attackers using packet sniffers (e.g., Wireshark).

Correct Method for Secure Remote Login in Python:

UseParamiko for SSH-based secure automation.

Example of logging in withParamiko (SSH)in Python:

import paramiko

ssh = paramiko.SSHClient()

ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect("192.168.1.1", username="admin", password="password")

stdin, stdout, stderr = ssh.exec_command("display version")

print(stdout.read().decode())

ssh.close()

Reference from Huawei HCIE-Datacom Documentation:

Huawei Security Best Practices – Avoiding Telnet and Using SSH for Secure Access

HCIE-Datacom Training Material – Network Automation with Python (Paramiko & Telnetlib)

On the2.4 GHzband, onlythree non-overlapping channelsexist:1, 6, and 11.

Inhigh-density WLAN scenarios, channels like1, 5, 9, and 13can be used withlower transmit powerto reduce co-channel interference — though they slightly overlap, they can work in dense deployments when managed properly.

On the5 GHzband, there are many non-overlapping channels. It’s recommended tostagger high and low channelsamong adjacent APs toavoid interference.

Correct answer: A. TRUE

Understanding SRv6 (Segment Routing over IPv6) Policies

????What is an SRv6 Policy?

Atraffic engineering (TE) mechanismused inSRv6-enabled networks.

Defines a set ofSegment Routing (SR) pathsthat direct packets through a predefined set of waypoints.

UsesSRv6 SIDs (Segment Identifiers)instead of MPLS labels.

????How Can SRv6 Policies Be Configured?

✅Static SRv6 Policy Configuration:

Manually configured by network administrators.

Used inpredictable, fixed network paths.

✅Dynamic SRv6 Policy Generation:

Created dynamically by anSDN controller(e.g.,Huawei iMaster NCE).

The controlleranalyzes network conditionsandadjusts paths automaticallybased on traffic load and link failures.

Why is the Answer TRUE?

✅SRv6 policies can be configured manually or dynamically delivered by a controller.

✅SDN-based SRv6 solutions improve network automation and traffic engineering efficiency.

Real-World Application:

Cloud Data Centers:Usesdynamic SRv6 policiesfor optimal traffic distribution.

5G Transport Networks:UsesSRv6 TE for low-latency service guarantees.

✅Reference:Huawei HCIE-Datacom Guide – SRv6 Policy and SDN Integration

Huawei Switch Deployment Methods in CloudCampus

✅A. DHCP Option 148– Used forautomatic device registrationin iMaster NCE-Campus.

✅B. CLI (Command-Line Interface)– Traditionalmanual configuration methodusing the command-line interface.

✅C. Web Interface–Web GUI-basedconfiguration for easy management.

✅D. Huawei Registration Center–Cloud-based automatic registration and provisioningfor plug-and-play deployment.

Reference from Huawei HCIE-Datacom Documentation:

Huawei CloudCampus Deployment Guide – Device Onboarding Methods

HCIE-Datacom Training Material – Zero-Touch Deployment (ZTP) in CloudCampus

Comprehensive and Detailed In-Depth Explanation:

A. Correct:OPS can use themaintenance assistantto triggerPython scriptsperiodically or based on events.

B. Correct:OPS supportsautomatic deploymentusing Python scripts to download software and configuration files.

C. Incorrect:OPS doesnot inherently provide local storagefor temporarily saving execution results when the network is disconnected. This would require additional programming logic in the script itself, which is not a built-in feature of OPS.

D. Correct:OPS can run scripts toautomatically check device healthand report the status.

Therefore, the incorrect statement isC.

Comprehensive and Detailed In-Depth Explanation:

Analyzing the output:

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

B. The subscription name is Sub1:Correct. Thesubscription nameis clearly shown asSub1.

C. The subscription mode is static subscription:Correct. Since theSub-stateisPASSIVE, it indicates astatic subscription.

D. The IP address of the device is 192.168.56.1:Incorrect. The IP address192.168.56.1shown in the output is thedestination IPwhere the telemetry data is sent, not the IP address of the device itself.

Huawei Open Programmability System (OPS) and HTTP Request Headers

HuaweiOPSallowsnetwork automation and programmabilitythroughHTTP-based APIs. When using Python scripts to sendHTTP requests to network devices, the requestheaders must specify the content formatfor data exchange.

✅B. Content-Type: text/json, Accept: text/json (Correct Answer)

Content-Type: text/json→ Specifies that the request bodycontains JSON-formatted data.

Accept: text/json→ Specifies that theresponse should be in JSON format.

Comprehensive and Detailed Explanation:

✔Fit APs require additional configurations before going online, such as:

AP authentication and onboardingthroughDHCP Option 148ormanual registration.

Firmware upgrade and provisioningfrom iMaster NCE-Campus.

Policy enforcementand VLAN assignment.

Since additional steps are required,Fit APs do not go online immediately, making the statementFALSE.

????Reference:Huawei HCIE Datacom – AP Registration and Authentication

Understanding Jinja2 Templates in Huawei SSP Packages

????What is Jinja2?

Jinja2 is atemplating engineused inHuawei SSP (Smart Script Package) automation.

It allowsdynamic configuration generationbased on variables and logic.

????Jinja2 Syntax Basics:

✅{% ... %}→ Used forcontrol structureslike loops and conditions.

✅{{ ... }}→ Used forvariable placeholders.

Example of a Jinja2 Template Using {% ... %} for a Loop:

{% for interface in interfaces %}

interface {{ interface.name }}

description {{ interface.description }}

{% endfor %}

????This template dynamically generates interface configurationsbased on a list of interfaces.

Why is the Answer TRUE?

✅{% ... %} is used for control structures in Jinja2 templates(e.g., loops, if-else statements).

✅Jinja2 templates are widely used in SSP for Huawei network automation.

Real-World Application:

Automated Network Configuration:Uses Jinja2 inHuawei SSP automation scripts.

Data Center & SDN Automation:Dynamically generatesVXLAN, BGP, and OSPF configurations.

✅Reference:Huawei HCIE-Datacom Guide – Jinja2 Templates in SSP Packages

The free mobility solution in Huawei iMaster NCE-Campus allows:

Centralized policy management via the controller

Security group-based policies, decoupled from IPs/VLANs

Automatic policy delivery, no need to configure repeatedly per device

Dynamic mapping of users and IPs via security group subscriptions

Exact Extract - Huawei iMaster NCE-Campus Solution White Paper:

“Free mobility uses security groups and centralized control to enable consistent policy enforcement, avoiding repetitive configurations and simplifying policy management.”

According to the displayed OSPF error statistics from the Huawei device, the key HELLO packet error shown is:

yaml

CopyEdit

2 : Netmask mismatch

This indicates that the OSPF adjacency formation is failing due to a subnet mask mismatch between the two OSPF neighbors on the corresponding interface (GigabitEthernet 0/0/0). OSPF uses the subnet mask in Hello packets to ensure that neighbors are in the same network. If the masks do not match, OSPF will not form an adjacency.

From the Huawei Official HCIE-Datacom Study Guide (Version 3.0) — under the OSPF Troubleshooting Section:

"Netmask mismatch: If the subnet mask configured on the interfaces of OSPF neighbors does not match, a 'Netmask mismatch' error occurs. OSPF requires neighbors to be on the same subnet to establish an adjacency. This is a common reason for failure in adjacency formation."

(Reference: Huawei HCIE-Datacom V3.0, OSPF Troubleshooting Chapter, Section 4.2 – OSPF Hello and Adjacency Establishment Issues)

Thus, among the given options:

A. Area type inconsistency would result in an area ID mismatch error, not netmask.

B. Authentication mismatch would show a bad authentication key or type error.

D. Hello interval mismatches would trigger a Hello timer mismatch error.

Only C. The IP address masks of the interfaces are inconsistent directly matches the actual error observed: Netmask mismatch.

????Analyze the Configuration:

[R2] acl 2000

[R2-acl-basic-2000] rule deny

[R2] ospf

[R2-ospf-1] area 1

[R2-ospf-1-area-0.0.0.1] filter 2000 import

[R2-ospf-1-area-0.0.0.1] quit

[R2-ospf-1] default-route-advertise always

????Understanding Key Concepts:

Type 3 LSAs (Inter-Area Routes):

Generated by ABRs to advertisesummary routesbetween areas.

Filtering Type 3 LSAsis possible using import filters (like in Area 1).

Type 5 LSAs (External Routes):

Flooded only within the same ASbutdo not enter stub or NSSA areas.

✅Breakdown of the Options:

A. Type 5 LSAs are flooded in Area 1→❌Incorrect

If Area 1 is astub or NSSA, thenType 5 LSAs are not allowed.

Although the diagram does not explicitly say Area 1 is a stub/NSSA,real deployments often use stub areas at the edge (like Area 1).

More importantly,the filter is applied to Area 1, and there isno redistributionof external routes into Area 1 in the config.

Therefore, Type 5 LSAs wouldnot be floodedthere.

B. Type 3 LSAs are not flooded in Area 1→✅Correct

The command filter 2000 import with ACL rule deny meansType 3 LSAs are filtered from Area 0 into Area 1.

C. Type 3 LSAs are not flooded in Area 2→✅Correct

There isno filter applied to Area 2, so thiscould be false,butsince the question asks for the incorrect statement, this is not the answer.

D. Type 5 LSAs are flooded in Area 2→✅Correct

Area 2 is not shown to be stub or NSSA, and there’s no filter or restriction configured.

Hence,Type 5 LSAs are allowedandflooded in Area 2.

✅Correct Answer: A. Type 5 LSAs are flooded in Area 1.

Comprehensive and Detailed In-Depth Explanation:

InOSPF, a Not-So-Stubby Area (NSSA) is a type of area that allows for the injection ofexternal routes(like a standard area) while maintaining some stub area characteristics.

Type 7 LSAs (NSSA External LSAs)are generated by ASBRs within an NSSA.

AnABRat the NSSA boundary translates theseType 7 LSAs into Type 5 LSAsto propagate them into the rest of the OSPF domain.

This translation is necessary becauseType 5 LSAsare the standard method for advertising external routes in OSPF.

Therefore, the statement isTRUE.

Let's dissect each option based on OSPFv3 LSA behavior from Huawei HCIE Datacom documentation.

✅ Option A: Correct

OSPFv3 uses Router LSAs (Type 1) to describe the local interfaces, links, and neighbors.

R1, as part of Area 0, will generate Router-LSAs and receive Router-LSAs from neighbors in the same area (R2 and R3 via switch S1).

Huawei Datacom Reference:

"Each OSPFv3 router originates a Type 1 Router LSA for each area it belongs to."

(Source: HCIE-Datacom Study Guide v3.0 - OSPFv3 Fundamentals)

❌ Option B: Incorrect (Correct Answer)

Link-LSAs (Type 8) are not sent between routers. They are only generated for each link on which the router has at least one neighbor. These LSAs are only flooded on the local link.

R1 cannot receive two Link-LSAs from R2 about both links. It can only receive the Link-LSA that R2 generates for the shared link with R1. The other link (e.g., to R4 in Area 1) is irrelevant to R1.

Huawei Datacom Reference:

"A Link LSA is generated by a router for each attached link and is sent only to the routers on the same link."

(Source: HCIE-Datacom Study Guide v3.0 - OSPFv3 LSA Types)

✅ Option C: Correct

On broadcast links, DRs generate Type 2 Network LSAs.

If R3 is the DR on the shared segment (with R1), R1 will have the Network-LSA from R3 in its LSDB.

Huawei Datacom Reference:

"The DR on a broadcast network generates a Type 2 Network LSA to describe all routers on that link."

(Source: HCIE-Datacom Study Guide v3.0 - OSPFv3 LSDB Construction)

✅ Option D: Correct

R2 connects Area 0 and Area 1, hence it's an ABR.

ABRs generate Type 3 Inter-Area-Prefix LSAs to advertise IPv6 prefixes from one area to another.

R2 advertises Area 1 prefixes to Area 0 routers (R1 and R3).

Huawei Datacom Reference:

"Inter-Area-Prefix LSAs (Type 3) are generated by ABRs to advertise IPv6 prefixes from one area into another."

(Source: HCIE-Datacom Study Guide v3.0 - ABR Functionality in OSPFv3)

SR-MPLS leverages IGP (OSPF/IS-IS) extensions to advertise Segment IDs (SIDs) and can also integrate with TE (Traffic Engineering) for bandwidth reservation using RSVP-TE or SR-TE.

Exact Extract – Huawei SR-MPLS Configuration Guide:

“SR-MPLS uses extensions in IGP to distribute label bindings and, combined with traffic engineering, supports bandwidth assurance and high-bandwidth services.”

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

Statically: Manual configuration.

Dynamically: Typically viaRSVP-TE.

Protocol roles:

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

OSPF / IS-IS: Act asIGP protocolsand provide TE-related link-state information (like bandwidth) butdo not establish LSPs themselves→❌

BGP: Used forroute advertisement, not forLSP setupin MPLS TE →❌

Correct answers: A, C, D

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

Comprehensive and Detailed Explanation:

✔SRv6 (Segment Routing over IPv6) Flavorsprovide additionalprocessing behaviorsfor SRv6End instructions.

✔PSP (Penultimate Segment Popping) Flavor:

PSP enables the penultimate node to remove the SRH (Segment Routing Header)before forwarding the packet to the last segment.

This reduces the processing overheadon the final segment node.

✔Correct End Instructions for PSP:

✅(A) End.X→ Cross-connect behavior between segments.

✅(C) End.T→ Transport encapsulation in SRv6.

✅(D) End→ Basic SRv6 endpoint behavior.

❌(B) End.BM is incorrect→ This is used forBinding Segment (BSID)behavior and does not support PSP.

????Reference:Huawei HCIE Datacom – SRv6 Flavors and End Instructions

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

In Huawei’sFree Mobility solution:

Authentication Point (AP): Identifies users and associates them with aSecurity Group Tag (SGT)upon access.

Policy Enforcement Point (PEP): Enforces policiesbetween different security groups, such as allowing or denying traffic.

Key points:

Ais correct — The PEP enforces inter-group access based on defined policies.

Bis incorrect — AP and PEPcan be on separate devices, offering deployment flexibility.

Cis incorrect — Thepolicy enforcementhappens at thePEP, not the AP. AP's job is to authenticate and tag traffic.

Dis correct — AP and PEP can be deployed ondifferent devices.

Correct answers: A, D

Comprehensive and Detailed In-Depth Explanation:

By default, OSPF does not automatically associate a domain ID with a process ID. The concept of "domain ID" is primarily used when redistributing routes between OSPF and BGP, particularly in MPLS VPN scenarios. The domain ID in OSPF helps maintain loop prevention and correct route advertisement between different OSPF domains. You can manually configure the domain ID using the domain-id command within the OSPF process view, but it is not inherently set to the process ID.

Option A: Correct — both terminal and interface security are important.

Option C: Correct —CAPWAP supports DTLSencryption for secure tunnel communication.

Option D: Correct — intranet security design considersboth wired and wireless.

Option B:Incorrect— traffic suppression (such as broadcast suppression) is implemented usingrate limiting or storm control,not by shutting down interfaces. Shutting down interfaces would disrupt legitimate traffic too.

Correct answer: B

ForOSPF neighbors to reach Full state, they must exchangeLSAs (Link State Advertisements) properlyand synchronize their databases.

Possible Causes Preventing OSPF from Entering Full State:

✅A. A link works abnormally

If thephysical or Layer 2 linkis unstable,OSPF Hello packetsmay be lost, preventing the Full state.

✅B. The OSPF network types on both ends of the link are inconsistent

OSPF network types (Broadcast, P2P, NBMA, etc.) must matchon both ends.

Example: If one router isP2Pand the other isBroadcast, adjacency issues occur.

✅C. The router IDs of neighbors are the same

Router ID conflicts prevent OSPF adjacencies from forming.

Each router must have aunique Router ID.

✅D. The OSPF MTU values of interfaces on both ends of the link are different

If MTU settings do not match,OSPF Database Description (DD) packets may be dropped, preventing Full state.

Reference from Huawei HCIE-Datacom Documentation:

Huawei OSPF Configuration Guide – Troubleshooting OSPF Neighbor Issues

HCIE-Datacom Study Material – OSPF Adjacency and Route Synchronization

IS-IS (Intermediate System to Intermediate System) protocolhas a limit on the size ofLink-State PDUs (LSPs).

Why Fragmentation?

LSPs contain routing and topology information.

If the LSPexceeds the maximum size, fragmentationallows the device to store and forward more routesby breaking them into smaller LSPs.

Key Point:IS-ISfragmentation is essentialin large-scale networks where routing tables grow beyond the default LSP size limit.

✅Reference:Huawei HCIE-Datacom Guide - IS-IS Protocol and Route Scaling

Comprehensive and Detailed In-Depth Explanation:

In SR-MPLS, ifprefix SIDs conflict, the following principles are applied:

Prefix with a smaller value (numerically lower SID) wins.

If the prefix length is the same, the lower SID value is selected.

In this case:

Both1.1.1.1/32 2 (A)and1.1.1.1/32 1 (B)have the same prefix length.

SinceSID 1is numericallysmallerthanSID 2,B (1.1.1.1/32 1)is selected.

The other routes (C and D) have different prefixes and do not directly conflict.

Comprehensive and Detailed Explanation:

✔BIER vs. PIM Multicast Routing:

BIER (Bit Index Explicit Replication)eliminates the need formulticast distribution trees (MDTs)by encodingreceiver information into the packet header.

PIM (Protocol Independent Multicast)requiresMDTs to manage multicast forwarding paths.

✔Correct Statements:

✅(A) BIER uses a Bitstring fieldin packet headers for forwarding.

✅(B) PIM builds MDTsto define multicast paths.

✅(C) BIER does NOT require MDTs, making it more scalable.

❌(D) Incorrect→ BIER does not require hop-by-hop join messages.

????Reference:Huawei HCIE Datacom – BIER and PIM Comparison