Huawei H12-821_V1.0 Exam Practice Test Instant Access

Question 1

The Origin attribute is used to define the origin of BGP path information. There are three types of Origin attributes. Which of the following lists the Origin attributes in descending order of priority?

AIGP > EGP > Incomplete

BIncomplete > IGP > EGP

CEGP > IGP > Incomplete

DIncomplete > EGP > IGP

Answer : A

Comprehensive and Detailed Step-by-Step

BGP Origin Attribute Priority:

The Origin attribute determines the source of the route and affects the selection of the best path.

The priority order is as follows:

IGP (i): Highest priority. Routes injected using the network command.

EGP (e): Lower priority. Routes learned from the EGP protocol.

Incomplete (?): Lowest priority. Routes redistributed into BGP from other protocols.

Correct Option:

A: IGP > EGP > Incomplete is the correct order of priority.

HCIA-Datacom Study Guide, Chapter: BGP Path Selection

Huawei BGP Routing Rules

Question 2

After which of the following parameters are modified does an IS-IS neighbor relationship need to re-established?

AThe cost of an IS-IS interface is changed.

BThe IP address of an ISIS interface is changed.

CThe level of an ISIS interface is changed.

DThe interval at which an IS-IS interface sends IIH packets is changed.

Answer : C

When the level of an IS-IS interface is changed, the adjacency must be re-established because IS-IS adjacencies are formed based on matching levels (Level-1, Level-2, or both). Other changes, such as cost or hello intervals, do not disrupt the existing adjacency but might impact routing metrics or timing .

Question 3

A router uses an advanced ACL to filter dat

a. The ACL configuration is shown below. Which of the following statements is false about the configuration?

csharp

CopyEdit

[Huawei] acl 3001

[Huawei-acl-adv-3001] rule permit icmp source 192.168.1.3 0 destination 192.168.2.0 0.0.0.255

AThe ACL permits ICMP packets from host 192.168.1.3 to host 192.168.2.200.

BThe ACL denies ICMP packets from host 192.168.1.2 to network segment 192.168.2.0/24.

CThe ACL permits IP packets from host 192.168.1.3 to network segment 192.168.2.0/24.

DThe ACL is a numbered ACL whose number is 3001.

Answer : C

Comprehensive and Detailed Step-by-Step

Understanding the ACL Configuration:

ACL Number: 3001 is an advanced ACL.

Rule Description: The rule permits ICMP packets with the following criteria:

Source IP: 192.168.1.3 (host-specific).

Destination IP: 192.168.2.0/24 (entire subnet).

Analysis of Each Option:

Option A: True. ICMP packets from 192.168.1.3 to 192.168.2.200 (within the subnet) are permitted.

Option B: True. Packets from 192.168.1.2 (not matching the source) are denied by default.

Option C: False. The ACL only permits ICMP packets, not general IP packets.

Option D: True. The ACL is identified by the number 3001.

HCIA-Datacom Study Guide, Chapter: ACL Filtering Rules

Huawei Advanced ACL Configuration

Question 4

In BGP, the Origin attribute is used to identify the origin of a route. Which of the following statements are true about the Origin attribute?

AIf a route is imported to BGP by the originator using the network command, the Origin attribute of the BGP route is displayed as i in the BGP routing table.

BIf a route is learned through EGP, the Origin attribute of this BGP route is displayed as ? in the BGP routing table.

CIf multiple routes carry the same destination address but different Origin attributes and all other route selection conditions are the same, BGP selects the optimal route according to the Origin attribute in the following order: IGP > EGP > Incomplete.

DThis attribute is a well-known mandatory attribute.

Answer : A, C, D

Comprehensive and Detailed Step-by-Step

Definition of the Origin Attribute:

The Origin attribute is a well-known mandatory attribute used to indicate the source of a route. It has three possible values:

i (IGP): The route was injected into BGP using the network command.

e (EGP): The route was learned from an EGP protocol (not commonly used now).

? (Incomplete): The route was redistributed into BGP from another routing protocol.

Analysis of Each Option:

Option A: Correct. When the network command is used, the Origin is set to i (IGP).

Option B: Incorrect. Routes learned from EGP have the Origin attribute set to e (EGP), not ? (Incomplete).

Option C: Correct. BGP prefers routes with the Origin attribute in the order: IGP > EGP > Incomplete.

Option D: Correct. The Origin attribute is a well-known mandatory attribute.

HCIA-Datacom Study Guide, Chapter: BGP Attributes

Huawei BGP Attribute Comparison

Question 5

A large number of routes typically exist in a BGP routing table, and transmitting such extensive routing information brings a heavy burden to a device. In order to address this problem, it is necessary to filter those routes to be advertised. You can configure a device to advertise only necessary routes or those that its peers require.

ATRUE

BFALSE

Answer : A

Comprehensive and Detailed Step-by-Step

BGP Route Filtering:

BGP provides flexible policies for route filtering to optimize routing table size and reduce network resource usage.

By configuring route filters, a device can advertise only required routes to peers, thereby improving efficiency.

Purpose of Filtering:

Reduces the routing table size.

Decreases CPU and memory usage on routers.

Limits unnecessary route propagation.

HCIA-Datacom Study Guide, Chapter: BGP Policy Control

Huawei BGP Route Filtering Configuration

Question 6

An ACL can be used to match routes or data, but cannot be used to match both the IP address prefix length and mask length.

ATRUE

BFALSE

Answer : B

Comprehensive and Detailed Step-by-Step

ACL Capabilities:

ACLs are versatile tools that can match:

Data packets: Using IP addresses, protocols, ports, etc.

Routes: ACLs can be used in route filtering, matching both IP prefix length and mask length.

Correct Statement:

ACLs can match both the IP address prefix length and mask length in route filtering applications.

HCIA-Datacom Study Guide, Chapter: ACL Applications

Huawei Route Filtering Using ACLs

Question 7

In BGP, Notification messages are used to request peers to resend routing information after routing policies are changed.

ATRUE

BFALSE

Answer : B

Notification Message Purpose

BGP Notification messages are used to report errors or terminate a connection. They do not request peers to resend routing information after routing policies are changed.

Routing updates following policy changes require manual resynchronization, not Notification messages.

HCIP-Datacom-Core Reference

The purpose and usage of Notification messages are discussed in the BGP operation chapters.

Huawei HCIP-Datacom-Core Technology V1.0 H12-821_V1.0 Exam Practice Test