Huawei Updated H12-811_V2.0 Exam Questions and Answers by mahdi

In STP, the root bridge is elected based on the lowest bridge ID (BID). A BID is composed of the bridge priority and the MAC address of the switch. The device with the smallest BID becomes the root bridge. Therefore, if an administrator wants SW2 to become the root bridge, the most direct and correct method is to configure a lower system priority on SW2, making option C correct.

Option A is incorrect because port priority affects port-role selection in some tie-breaking scenarios, but it does not determine root-bridge election. Option B is the opposite of what is required, because a higher system priority makes the BID larger and reduces the chance of being elected as root. Option D is also incorrect because root path cost is used by non-root bridges to select the best path to the existing root bridge; it does not determine which switch becomes the root bridge in the first place. HCIA-Datacom stresses that bridge priority tuning is the standard administrative method used to control root bridge placement in campus networks for stable and predictable Layer 2 topology design.

Before PC1 is moved, PC2 successfully communicates with it, so SW1 learns PC1 ' s MAC address on GE1/0/1. The dynamic MAC aging time is 300 seconds, and the cable move is performed immediately. Therefore, when PC2 sends the next frame to PC1, SW1 can still have the old destination MAC entry pointing to GE1/0/1. The question then states that GE1/0/1 is connected to another switch, so the port remains physically usable. SW1 follows the existing MAC table entry and forwards the frame out GE1/0/1 toward that new connection; it does not simply discard the frame. If PC1 subsequently transmits from GE1/0/2, SW1 can relearn the same source MAC on the new interface and update the entry, restoring correct forwarding. The core point is that dynamic MAC entries do not immediately disappear merely because the end station is physically moved when the original interface remains Up. Accordingly, the statement that SW1 discards the frame is FALSE, option B.

A router works mainly at the network layer . When it receives a frame, it removes the Layer 2 header and trailer, examines the destination IP address in the Layer 3 header, consults the routing table, selects the outgoing interface, and then re-encapsulates the packet into a new Layer 2 frame for the next hop. Therefore, statement B is true and is not part of the answer.

Statement A is false because the router does not create a new destination IP address during normal forwarding. The source and destination IP addresses remain unchanged end to end unless special functions such as NAT are used. Statement C is false because routing-table lookup is based on the destination IP address, not on TCP or UDP port numbers. Statement D is also false because normal IP routing does not inspect application-layer content to determine the outgoing interface. That decision is made from the network-layer destination address and the routing table. This question tests the layered forwarding logic of routers in TCP/IP networks.

The command output in the exhibit shows that both AP radios are enabled, so a disabled radio is not supported by the evidence. The 5 GHz radio has relatively low channel utilization, while the 2.4 GHz radio reports channel utilization of approximately 90 percent. Such a high utilization value indicates that the air interface is heavily occupied by transmissions or interference. Huawei WLAN troubleshooting guidance identifies a busy air interface and a heavily loaded AP as possible causes of STA association failures because management and authentication frames may be delayed or lost when contention is severe. The displayed radio information alone does not prove that the affected STAs are in a blacklist or absent from a whitelist; those conditions require separate STA or VAP access-control information. Therefore, option A is the only choice directly supported by the command output. The correct troubleshooting interpretation is that excessive channel utilization on the radio can make the air interface busy and prevent some STAs from completing association successfully. The verified answer is A.