H12-821_V1.0 Exam Dumps - HCIP-Datacom-Core Technology V1.0

IGMP Version Mismatch

If the IGMP snooping version on the device is earlier than the IGMP version on user hosts, the device may fail to parse IGMP Report messages correctly. As a result, the device forwards these messages only to router ports without generating group member ports or forwarding entries.

Consequently, users cannot receive multicast data.

HCIP-Datacom-Core Reference

Multicast and IGMP snooping behaviors under mismatched conditions are described in the multicast configuration chapters​​.

Comprehensive and Detailed in-depth Step-by-Step Explanation:The Network Entity Title (NET) is a unique identifier assigned to an IS-IS router. It is derived from the Network Service Access Point (NSAP) address and consists of the following components:

Area Address:

Identifies the area in which the router resides.

Multiple routers in the same IS-IS area must have the same area address.

System ID:

Uniquely identifies the router within the IS-IS area.

The System ID is typically derived from the router's loopback IP address or another unique value.

SEL (Selector Field):

The SEL field is always set to 00 for IS-IS NETs.

The NET is used by IS-IS for route calculation and to identify the router within the IS-IS domain. Therefore, the statement is TRUE.

References:

Huawei HCIA-Datacom Study Guide, Chapter on "IS-IS Addressing".

RFC 1195 – Use of OSI IS-IS for Routing in TCP/IP and Dual Environments.

When a Huawei firewall receives a packet that does not match any existing session table entry, it discards the packet. This is part of the default firewall policy, which ensures that unrecognized traffic is treated as a potential security risk and blocked. This behavior is vital for preventing unauthorized access and mitigating external attacks. The feature aligns with Huawei's default security strategies as detailed in their firewall operation manuals ​.

The Link State ID in a Type 3 LSA (Summary LSA) indicates the network or subnet being summarized, not the router ID of an ABR. All other statements accurately describe OSPF functionality, making D the false statement ​.

ï‚· ACL Modification

Named ACLs can be modified after their creation. Unlike numbered ACLs, named ACLs provide greater flexibility for editing individual rules without deleting the entire ACL.

Therefore, the statement is incorrect.

ï‚· HCIP-Datacom-Core Reference

The flexibility and editability of named ACLs are discussed in the ACL configuration sections​​.

Comprehensive and Detailed in-depth Step-by-Step Explanation:OSPF routers establish neighbor relationships and progress through various states during the adjacency formation process. The ExStart state is where routers negotiate the master and slave roles. This negotiation is critical because the master initiates the Data Description (DD) packet exchange process.

Here’s a breakdown of the relevant OSPF states:

ExStart State:

This is the phase where the routers determine which one will act as the master and which will be the slave.

The decision is based on the Router IDs of the two routers. The router with the higher Router ID becomes the master.

Exchange State:

After the master-slave roles are established, the routers exchange DD packets. These packets contain summaries of the LSAs in their respective LSDBs.

2-way State:

This state indicates that bidirectional communication has been established between the two routers, but it occurs before master-slave negotiation.

Init State:

This is an early state where a router has sent a Hello packet to its neighbor but has not yet received a Hello packet in response.

Key Point:The negotiation of master and slave roles happens exclusively in the ExStart state, making D. ExStart the correct answer.

References:

Huawei HCIA-Datacom Study Guide, Chapter on "OSPF Neighbor States".

RFC 2328 – OSPF Version 2 (Section 10.8).

By default, Huawei firewalls create security zones named untrust, dmz, trust, and local. These zones facilitate security policies for inbound, outbound, and inter-zone traffic control ​.

In the provided configuration, IS-IS is enabled on Loopback0 but not on Loopback3 of R2. As a result, R2 will advertise the route 10.0.2.2/32 (from Loopback0) to R1 through IS-IS. However, the route 10.0.2.3/32 will not be advertised because IS-IS is not enabled on that loopback interface. The import-route direct command does not override this behavior ​.