H12-811_V2.0 Exam Dumps - HCIA-Datacom V2.0

This statement is true . ARP is a Layer 2 broadcast-based protocol used to resolve an IPv4 address into a MAC address within the same broadcast domain. If two PCs are connected to the same switch but cannot learn each other’s ARP entries, one likely reason is an incorrect VLAN configuration .

For example, if PC1 and PC2 are placed in different VLANs, or if one interface is configured with the wrong access VLAN, ARP broadcast frames from one PC will not reach the other PC because VLANs separate Layer 2 broadcast domains. As a result, the ARP request will not be received by the peer, and the MAC address cannot be resolved. Other causes may also exist, such as incorrect IP addressing, port isolation, or security policies, but VLAN misconfiguration is a very common and valid cause in campus switching scenarios. HCIA-Datacom teaches that ARP communication depends on correct Layer 2 domain membership, and VLAN planning or interface configuration errors often directly affect host-to-host communication even when both hosts are physically connected to the same switch.

All four options are possible causes of FTP login failure, so the correct answer is A, B, C, and D.

Option A is correct because if the FTP server function is not enabled on the Huawei device, the device cannot provide FTP services and the client cannot log in. Option B is also correct because if the authorized directory is not specified for the FTP user, the user may not be able to complete login or access file services properly, depending on the FTP user configuration requirements. Option C is correct because an FTP user account must be configured with the required username and password; otherwise, authentication cannot succeed. Option D is also correct because if the network between the FTP client and the device is unreachable, the client cannot establish the FTP connection at all.

In HCIA-Datacom troubleshooting, FTP login failure is usually checked from four aspects: service enablement, user configuration, permission or directory authorization, and network connectivity. This question tests standard remote maintenance troubleshooting logic for file transfer services on Huawei network devices.

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