Free Huawei H12-811_V2.0 Practice Exam with Questions & Answers | Set: 2

In the standard TCP/IP forwarding model, transport-layer headers such as TCP and UDP headers are added by the source host and are mainly interpreted by the destination host. Routers that forward packets between the source and destination operate primarily at the network layer , using the destination IP address in the IP header to make forwarding decisions. Therefore, under normal routing behavior, routers do not process transport-layer header information when deciding how to forward packets.

This is a key concept in layered communication. The source host encapsulates application data with a transport-layer header, then with an IP header, and finally with a data-link header. Each router along the path removes only the Layer 2 frame header, checks the Layer 3 destination IP information, decrements TTL, recalculates the IP header checksum when required, and forwards the packet. The transport-layer content remains unchanged in normal forwarding. HCIA-Datacom uses this principle to explain end-to-end communication and layer responsibilities. Although advanced devices may inspect higher-layer information for security or policy purposes, standard router forwarding in the basic TCP/IP model does not depend on transport-layer processing.

A /28 subnet mask corresponds to 255.255.255.240, which means each subnet contains 16 IP addresses . The subnet boundaries in the last octet increase in steps of 16: 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, and so on. The host address 192.168.1.147 falls within the subnet range 192.168.1.144 to 192.168.1.159 .

In that subnet, the network address is 192.168.1.144, the usable host range is 192.168.1.145 through 192.168.1.158, and the broadcast address is 192.168.1.159. Therefore, option C is correct. Option D is the first usable host address, not the broadcast address. Option A is just another usable host address. Option B would be the broadcast address only for a /24 network, not for a /28. HCIA-Datacom requires learners to master subnetting because it is essential for IP planning, gateway deployment, route summarization, and troubleshooting Layer 3 communication issues in campus and enterprise networks.

When two OSPF routers reach the Full state, it means that adjacency establishment has been successfully completed and the routers have synchronized the necessary link-state information for that area. For this to happen, the two routers must have different router IDs, so option A is correct. They must also belong to the same OSPF area on the interfaces used to form the adjacency, making option B correct. Once adjacency reaches Full state, the routers have synchronized their link-state databases for that area, so option D is also correct.

Option C is incorrect because the OSPF process ID is only locally significant on a device. Two neighboring routers do not need to use the same process ID to establish adjacency. HCIA-Datacom teaches that OSPF neighbor formation depends on matching parameters such as area ID, network type, hello/dead timers, authentication settings, and subnet consistency, but not on the locally configured process number. This question is important because many learners mistakenly believe the process ID must match between devices, while in fact OSPF uses protocol parameters exchanged in packets rather than local process labels to form neighbor relationships.

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This scenario describes the classic router-on-a-stick inter-VLAN routing design. A single physical interface on R1 connects to switch S1, and multiple sub-interfaces are created on that physical interface to serve as gateways for multiple VLANs. Therefore, if R1 provides Layer 3 gateway functions for VLAN 2 and VLAN 3, sub-interfaces such as GE0/0/1.2 and GE0/0/1.3 must be configured, so option A is correct.

Because PC2 and PC3 are connected to switch S1, S1 learns their source MAC addresses dynamically and stores them in its MAC address table, making option B correct. R1 receives tagged frames from different VLANs on the trunk link and, through its sub-interfaces, can identify and terminate frames for VLAN 2 and VLAN 3, so option C is also correct. Option D is incorrect because hosts in different VLANs do not need to be connected to different physical switches; VLAN separation is logical, not necessarily physical. HCIA-Datacom uses this deployment to explain inter-VLAN communication, 802.1Q trunking, and flexible campus gateway design using limited router interfaces.

This statement is false . In classic STP, when a non-root switch detects a topology change, it does not continuously send configuration BPDUs upstream to notify the root bridge. Instead, it sends a Topology Change Notification (TCN) BPDU toward the root bridge through its root port. Each upstream switch acknowledges the TCN and forwards it further until it reaches the root bridge.

After the root bridge receives the topology change notification, the root bridge sets the Topology Change (TC) flag in its configuration BPDUs, and those configuration BPDUs are then propagated throughout the network. Therefore, topology-change notification and normal configuration BPDU transmission are different functions. The statement is wrong because it confuses TCN BPDUs with configuration BPDUs , and also inaccurately describes the notification behavior. HCIA-Datacom requires learners to distinguish between these BPDU types and understand how STP reacts to topology changes by accelerating MAC address aging and informing the network through the root bridge. This process helps the Layer 2 topology converge and reduces long-lasting forwarding inconsistencies after a link or port-state change.

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On Huawei devices, the undo command is used to remove a previously applied configuration, disable a function, or restore a parameter to its default state. In option B , undo ip address is a valid interface-view command that removes the IP address configured on the interface. In option C , undo portswitch is also a valid interface command on switch interfaces that converts a Layer 2 interface into a Layer 3 interface when supported by the device. In option D , undo sysname restores the device name to the default hostname, which is valid in system view.

Option A is incorrect because system-view is a command used to enter system view from user view, but undo system-view is not a valid command for exiting that view. Exiting system view is done with commands such as quit, return, or by using shortcut keys. This question checks the understanding that undo only applies to configurable features and parameters, not to view-switching commands in the CLI hierarchy.

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Comprehensive and Detailed 150 to 200 words of Explanation From Datacom knowledge:

The false statement is B . From the AAA configuration output, the value of Remote-admin-user block time is clearly shown as 5 Min(s) , which means the account lockout duration is 5 minutes , not 30 minutes.

Option A is true because Remote-admin-user block retry-time : 3 indicates that after 3 consecutive authentication failures , the account will be blocked. Option C is also true because the displayed Domain Name Delimiter is @ , which is the separator used in usernames such as user@huawei.com. Option D is true as well because the output shows Local-user : total: 512 used: 2 , meaning that the device supports a maximum of 512 local users , and currently 2 local users have been created.

This question checks the ability to correctly read AAA configuration output on Huawei devices. In HCIA-Datacom knowledge, it is important to distinguish between retry interval , retry count , and block time , because these values represent different security control parameters and are often confused during troubleshooting or configuration review.

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This statement is true . In SNMP, both Trap and Inform messages are used by managed devices to proactively report alarms or events to the Network Management System (NMS) . However, their reliability behavior is different. A Trap is sent without requiring an acknowledgment from the NMS. Once it is transmitted, the sender does not confirm whether the manager actually received it.

By contrast, an Inform Request requires the NMS to send a response confirming receipt. If the managed device does not receive the acknowledgment within the expected time, it can retransmit the Inform message. Because of this, Inform is considered more reliable than Trap, although it also introduces slightly more overhead. HCIA-Datacom highlights this difference when explaining SNMP-based monitoring and alarm reporting. In real network O & M scenarios, the choice between Trap and Inform depends on the required balance between reliability and simplicity. This question tests a very standard SNMP knowledge point: Trap is unacknowledged , while Inform is acknowledged . Understanding this distinction helps network engineers choose suitable alarm reporting mechanisms in enterprise monitoring platforms.

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