Free Access to Huawei.H12-891_V1.0.v2026-06-05.q295 with Valid Practice Test (Page 32)

Question 151

There are multiple SR-MPLS TE tunnel protection mechanisms. FRR (Fast Reroute) constructs a virtual node to convert multiple identical route advertisement nodes into a single route advertisement node, and then computes the backup next hop of the virtual node based on the TI-LFA algorithm. In this way, traffic can be quickly switched when a fault occurs.
What is the name of this protection mechanism?

Question 152

What can be determined from the following figure?

A.R3 must be a Level-2 device.
B.The device role of R3 cannot be determined.
C.R3 must be a Level-1-2 device.
D.R3 must be a Level-1 device.

Correct Answer: C

To determine R3's role (Level-1, Level-2, or Level-1-2) based on the provided output of the display ipv6 routing-table protocol isis command on R3, we need to analyze the IS-IS routing information and understand IS-IS hierarchy and behavior, particularly in the context of IPv6 routing. Let's break it down step by step:
Understanding the IS-IS Levels and Hierarchy:
IS-IS (Intermediate System to Intermediate System) is a link-state routing protocol that supports a two-level hierarchy:
Level-1: Routers within the same area, responsible for intra-area routing. Level-1 routers only maintain routing information for their area and rely on Level-1-2 routers to reach other areas.
Level-2: Routers that form the backbone, connecting different areas for inter-area routing. Level-2 routers maintain routing information across areas.
Level-1-2: Routers that operate both at Level-1 (within their area) and Level-2 (to connect to other areas). These routers act as boundary routers between Level-1 areas and the Level-2 backbone.
A router's role (Level-1, Level-2, or Level-1-2) determines which types of adjacencies it can form and what routing information it advertises or receives.
Analyzing the Output:
The output shows R3's IPv6 routing table with routes learned via IS-IS, specifically:
Destination: 2082:EDFC:DDCC::B824:0/127, Protocol: ISIS-L1
This route is learned via IS-IS Level-1 (ISIS-L1), indicating that R3 has a Level-1 adjacency and is receiving or advertising routes within its area.
The next hop (FE80::2E0:FCFF:FE45:6A3E) and interface (GigabitEthernet0/0/0) suggest this route is intra-area.
Destination: 2082:EDFC:DDCC::B891:0/127, Protocol: ISIS-L2
This route is learned via IS-IS Level-2 (ISIS-L2), indicating that R3 has a Level-2 adjacency and is receiving or advertising routes for inter-area or backbone routing.
The next hop (FE80::2E0:FCFF:FE50:406F) and interface (GigabitEthernet0/0/1) suggest this route is for a different area or the backbone.
Both Level-1 and Level-2 routes are present in R3's routing table, which provides critical insight into R3's role.
Determining R3's Role:
Level-1 Routers:
Level-1 routers only participate in Level-1 adjacencies and maintain routing information for their area. They do not have Level-2 routes or adjacencies unless connected to a Level-1-2 router. Since R3 has a Level-2 route (ISIS-L2), it cannot be exclusively a Level-1 router.
Level-2 Routers:
Level-2 routers focus on inter-area routing and typically do not maintain Level-1 routes unless they are also configured as Level-1-2. Since R3 has a Level-1 route (ISIS-L1), it cannot be exclusively a Level-2 router.
Level-1-2 Routers:
Level-1-2 routers operate both at Level-1 (for intra-area routing) and Level-2 (for inter-area routing). They can form adjacencies with both Level-1 and Level-2 neighbors and maintain both types of routes. The presence of both ISIS-L1 and ISIS-L2 routes in R3's routing table indicates that R3 is participating in both Level-1 and Level-2 adjacencies, making it a Level-1-2 router.
Evaluating Each Option:
A . R3 must be a Level-2 device.
This is incorrect because R3 has ISIS-L1 routes, indicating it is also participating in Level-1 adjacencies, which Level-2-only devices do not do. Level-2 devices focus solely on inter-area routing and do not maintain Level-1 routes.
B . The device role of R3 cannot be determined.
This is incorrect because the presence of both ISIS-L1 and ISIS-L2 routes in the routing table clearly indicates R3's role. The combination of Level-1 and Level-2 routes confirms R3 is a Level-1-2 router.
C . R3 must be a Level-1-2 device.
This is correct. The routing table shows both ISIS-L1 (Level-1) and ISIS-L2 (Level-2) routes, meaning R3 is operating as both a Level-1 and Level-2 router, which defines a Level-1-2 device.
D . R3 must be a Level-1 device.
This is incorrect because R3 has ISIS-L2 routes, indicating it is also participating in Level-2 adjacencies, which Level-1-only devices do not do. Level-1 devices only maintain intra-area routes and rely on Level-1-2 routers for inter-area reachability.
Additional Considerations:
The Flags: D in the output typically indicates a directly connected route or a route downloaded to the forwarding table, but it does not affect the determination of R3's IS-IS level.
The preference (15) and cost (20) are standard for IS-IS routes and do not impact the level determination.
In Huawei's IS-IS implementation, routers can be configured explicitly as Level-1, Level-2, or Level-1-2 using commands like isis level-1-2 under the IS-IS process. The presence of both Level-1 and Level-2 routes confirms R3's configuration as Level-1-2.
Huawei HCIE-Datacom Context:
According to Huawei HCIE-Datacom documentation, IS-IS routers can operate at different levels, and the routing table's protocol type (ISIS-L1 or ISIS-L2) indicates the level of adjacency. A router with both Level-1 and Level-2 routes is necessarily a Level-1-2 device, as it participates in both intra-area and inter-area routing.
The display ipv6 routing-table protocol isis command on Huawei devices shows routes learned via IS-IS, and the protocol type (L1 or L2) directly reflects the router's role in the IS-IS hierarchy.
Conclusion:
Based on the presence of both ISIS-L1 and ISIS-L2 routes in R3's IPv6 routing table, R3 must be a Level-1-2 device, as it is participating in both Level-1 (intra-area) and Level-2 (inter-area) adjacencies. Therefore, the correct answer is C.
References to Huawei HCIE-Datacom Documents:
Huawei HCIE-Datacom V1.0 Training Material, Chapter on IS-IS Configuration and Hierarchy.
Huawei NE Series Router Configuration Guide, IS-IS Section (Level-1, Level-2, and Level-1-2 Operations).
Huawei Technical Whitepaper on IS-IS Protocol, discussing IPv6 Routing and Level Determination.

Question 153

Which of the following technologies can be used to isolate users in the same VLAN?

A.Super VLAN
B.Port isolation
C.IPSG
D.Ethernet port security

Question 154

There can be multiple nodes under a route -policy, different node numbers are identified by nodes, and each node can have multiple if-match and apply clauses, which of the following descriptions are wrong ?

A.The relationship between the if-match clauses under each node is "and"
B.The relationship between different nodes is an "and" relationship
C.There is an "or" relationship between different nodes
D.The relationship between the if-match clauses under each node is "or"

Question 155

What type of prefix does a router running BGP advertise to its IBGP neighbor (assuming the router is not configured as a route reflector)? (radio).

A.Prefixes are learned through EBGP neighbors, or prefixes are learned locally through network or routing introduction
B.The prefix is learned through an EBGP neighbor, or the prefix is learned from an from RR
C.A prefix that exists in the routing table
D.Prefixes are learned through other BGP neighbors, or prefixes are learned locally through network or routing introduction
E.Prefixes are learned through other IBGP neighbors, or prefixes are learned from EBGP neighbors, or prefixes are learned through routing introduction

Question 151

Question 152

Question 153

Question 154

Question 155

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