H12-811 — frequently asked questions

To ensure the most efficient paths are selected. Lower cost links are preferred, so high-speed links become the primary forwarding paths.

Yes, administrators can manually configure port costs on switches if the default auto-calculated values do not meet design requirements.

The PVID (Port Default VLAN ID) is the default VLAN identifier assigned to a switch port. It is used to classify incoming untagged frames into a specific VLAN.

No. Access ports associate untagged frames with the PVID but do not add tags to them upon egress. Hybrid ports can be configured to accept untagged frames without adding tags or to drop them entirely.

No, IEEE 802.11ac operates exclusively on the 5 GHz frequency band. It does not support the 2.4 GHz band.

IEEE 802.11n (Wi-Fi 4) and IEEE 802.11ax (Wi-Fi 6) support both 2.4 GHz and 5 GHz bands. 802.11ac is limited to 5 GHz.

The S bit stands for Bottom-of-Stack. It indicates whether the current label is the last one in the stack.

No. ToS is in the IP header. EXP is in the MPLS header and carries similar QoS priority information but is distinct.

No. OSPF calculates the shortest path using a cost metric, typically derived from interface bandwidth. Hop count is the metric used by RIP.

OSPF maintains a complete map of the network topology using LSAs. Each router runs the Dijkstra SPF algorithm independently to build a loop-free tree.

An Alternate port provides a backup path to the Root Bridge and replaces a failed Root Port. A Backup port provides a backup path to a network segment and replaces a failed Designated Port.

They handle different types of redundancy. Alternate ports deal with upstream failures toward the root, while Backup ports deal with downstream loop prevention on shared segments where two ports connect to the same LAN.

Use the 'clock datetime' command to manually set the system time on Huawei AR routers.

The save command stores the configuration in the startup-configuration file on the device's flash memory.

While Managed Objects exist within SNMP, they are instances of data stored in the MIB. The MIB itself is the structural component (database/schema) that composes the system architecture.

The NMS (Network Management Station) acts as the manager that initiates requests to agents and processes the responses or traps received from managed devices.

Indirectly. The Eth-Trunk depends on its local member interfaces. If the peer disables a link, the local link usually goes down due to link loss. The Eth-Trunk state depends on how many local members remain active.

If all member interfaces in an Eth-Trunk are down, the Eth-Trunk interface itself transitions to the Down state because it has no active paths for traffic.

The IHL (Internet Header Length) field is 4 bits, allowing a maximum value of 15. Since each unit is 4 bytes, 15 * 4 = 60 bytes maximum.

It is impossible under the IPv4 standard because the total header cannot exceed 60 bytes. If more data is needed, it must go into the payload, not the header.

No. 802.1X is a network access control protocol that uses AAA services (like RADIUS) for authentication. It is not a selectable mode within the AAA configuration itself.

The 'None' mode allows users to access the device without providing any credentials. This is typically used for testing or in trusted environments where authentication is handled externally.

No. Multipath is a general term. Equal-cost multipath (ECMP) is a specific type where metrics are identical. Unequal-cost multipath (UCMP) exists in some advanced configurations.

Because the question does not specify that the routes have the same metric. 'Multipath routes' is the generic term for any scenario involving multiple valid paths to a destination.

Yes, on broadcast and NBMA networks, OSPF automatically elects a DR and BDR during adjacency formation based on priority and Router ID.

No. Setting the interface priority to 0 disqualifies the router from both DR and BDR roles. It can only participate as a DROTHER.

No. You must first enter the OSPF process view using 'ospf [process-id]' before configuring areas.

No, they are functionally identical. Huawei VRP accepts both decimal and dotted-decimal formats for Area IDs.