H12-831_V1.0 Exam Dumps : HCIP-Datacom-Advanced Routing & Switching Technology V1.0

1. Understanding VLAN Aggregation in Huawei Switches

VLAN aggregation is a technique that groups multiple VLANs (sub-VLANs) under a single Super-VLAN.

Super-VLANs do not have member interfaces but include multiple Sub-VLANs that share a common gateway (VLANIF interface).

2. Inter-Sub-VLAN Communication Requirement

By default, hosts in different sub-VLANs cannot communicate directly.

To enable communication between different sub-VLANs within the same Super-VLAN, an inter-sub-VLAN proxy must be enabled.

This is done using the inter-sub-vlan-proxy enable command in the VLANIF interface of the Super-VLAN.

3. Correct Command Usage

The command format is:

shell

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supervlan inter-sub-vlan-proxy enable

This command must be executed under VLANIF 10, corresponding to the Super-VLAN.

4. Why is the Answer "supervlan"?

The missing parameter in the command should be supervlan, because it is used to enable communication between Sub-VLANs under a Super-VLAN.

This is a specific Huawei command used in HCIP-Datacom-Advanced Routing & Switching Technology certification.

Comprehensive and Detailed In-Depth Explanation:

Step 1: Understanding OSPF Areas and Summarization

Loopback0 on R5 has IP 10.0.5.5/32 and is advertised into OSPF.

The abr-summary 10.0.5.0 255.255.255.0 command is applied in area 2 on R1, which means:

Instead of advertising individual host routes (like 10.0.5.5/32), R1 advertises the summarized route 10.0.5.0/24 into Area 0 (Backbone).

This summarized route is then propagated into other areas via Area 0 (Backbone).

Step 2: Analyzing the Routing Table of Each Router

R5 (Originating Router in Area 2)

R5 only knows 10.0.5.5/32 because it's the originating router.

The abr-summary command does not affect R5 itself.

❌ R5 does not have 10.0.5.0/24.

R1 (ABR for Area 2, Summarizing the Route)

R1 creates and advertises 10.0.5.0/24 into Area 0.

This summary route is sent to other areas via Area 0.

R2 (Connected to Area 0 & Area 1)

Since R2 is part of Area 0 (Backbone), it receives 10.0.5.0/24 from R1.

✅ R2 has 10.0.5.0/24 in its routing table.

R3 (Connected to Area 0 & Area 2)

Since R3 is also connected to Area 0, it receives the summary route 10.0.5.0/24 from R1.

✅ R3 has 10.0.5.0/24 in its routing table.

R4 (In Area 1, which is not directly connected to Area 2)

R4 belongs to Area 1, and unless explicitly advertised through inter-area summarization, it will not have 10.0.5.0/24.

Since no specific mention of summary advertisement into Area 1 is made, R4 does not get 10.0.5.0/24.

❌ R4 does not have 10.0.5.0/24.

Final Answer: ✅ R2, R3 (Option B, C)

References:

HCIP-Datacom-Advanced Routing & Switching Technology V1.0 – OSPF Route Summarization

OSPF Inter-Area Route Advertisement via ABRs

OSPF Backbone (Area 0) Behavior and Route Distribution