Huawei H12-811 MAC Address Table: Which Forwarding Statement Is True?

H12-811 By islever Editorial Last updated

Ethernet Switching Basics

Short answer

C Since 5489-989d-1d30 is in the MAC table on Eth0/0/1, the frame from 5489-9885-18a8 to 5489-989d-1d30 is forwarded out Eth0/0/1, not Eth0/0/2.

Question

Refer to the following MAC address table of a switch. Which of the following statements is true?
Exhibit: Huawei H12-811 MAC Address Table: Which Forwarding Statement Is True?
  1. When the switch restarts, the MAC address learned by Eth0/0/3 needs to be relearned.
  2. When the switch restarts, the MAC address learned by Eth0/0/2 does not need to be relearned.
  3. The switch forwards the data frame with the source MAC address 5489-9885-18a8 and destination MAC address 5489-989d-1d30 through Eth0/0/1. Correct Answer
  4. The switch forwards the data frame with the source MAC address 5489-9811-0b49 and destination MAC address 5489-989d-1d30 through Eth0/0/2.

Key Takeaways

The exam tests whether you separate MAC learning from forwarding: known destinations select the egress port, while static entries survive reboot and dynamic entries are relearned.

This H12-811 MAC address table question tests destination-MAC forwarding and static versus dynamic entries. The correct choice is C, because 5489-989d-1d30 is reached through Eth0/0/1 regardless of the frame's source MAC.

Common mistake: The most tempting wrong answer is D, which assumes the source MAC 5489-9811-0b49 or a different table entry sends the frame out Eth0/0/2; the destination 5489-989d-1d30 is actually on Eth0/0/1.

Expert Analysis

The decisive lookup is the destination MAC. The question asks which statement is true, and the table maps 5489-989d-1d30 to Eth0/0/1. A switch uses the destination MAC in a frame to choose the egress port. Therefore a frame whose destination is 5489-989d-1d30 leaves through Eth0/0/1 regardless of whether its source is 5489-9885-18a8 or 5489-9811-0b49. That makes option C the true statement and option D false, because D sends the same destination out Eth0/0/2.

Entry type tests the reboot claims. The exhibit's Eth0/0/3 entry is static, while Eth0/0/2 is dynamically learned. A static MAC entry is part of the configuration and does not have to be relearned after a restart; a dynamic entry is not retained and must be relearned. Thus option A is false: it says the Eth0/0/3 MAC needs relearning when the relevant entry is static. Option B is also false in the opposite direction: it says the Eth0/0/2 MAC does not need relearning, but that entry is dynamic.

Source MACs do not override egress. Comments on this item note that forwarding is based on the destination MAC, and that the destination in C and D is on Eth0/0/1, not Eth0/0/2. The source address is used for MAC learning or for updating the table; it does not decide the outgoing interface when a valid destination entry exists. If a source MAC is already in the table on another port, the switch may update the entry, but the current frame's known destination still directs the frame to the destination port. The 'true' qualifier therefore selects C: it correctly pairs the destination 5489-989d-1d30 with Eth0/0/1; A and B misstate reboot persistence by port, and D uses the wrong egress port.

Exam Strategy

When a MAC-table question asks for the true statement, first identify the destination MAC and its table port; forwarding is destination-driven, so any option that changes egress because of a different source is a trap. Then check the entry type: static entries survive a reboot, dynamic entries must be relearned. Apply both checks to every option before selecting.

Frequently Asked Questions

Does a switch use the source or destination MAC address to select the outgoing port?

The destination MAC is looked up in the MAC address table to choose the egress port; the source MAC is used for learning and table updates, not for overriding a known destination.

Why is option A false for the Eth0/0/3 MAC entry?

The Eth0/0/3 entry is static in the exhibit. Static MAC entries remain configured across a restart, so they do not need to be relearned; dynamic entries do.

What happens to dynamically learned MAC entries after a switch restart?

Dynamic MAC entries are not retained across a restart and must be relearned as traffic arrives; this is why the Eth0/0/2 statement in B is false.

More H12-811 FAQ →

Community Votes

C
67%
A
33%

67% of anonymous learners picked answer C. Votes are pick records left by other test-takers — they are not the verified answer.

Discussion 3 contributions

Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.

From public community threads 3

  1. Fmoura17 👍 1 Answered A
    Why A is correct: The MAC on Eth0/0/3 is static — static entries survive reboots and don't need relearning. But among all options, A is the only true statement because: B — Eth0/0/2 is dynamic, so it must be relearned after restart. C — Frames are forwarded based on destination MAC, so it goes out Eth0/0/1, not Eth0/0/1 from source logic. D — Destination 5489-989d-1d30 is on Eth0/0/1, not Eth0/0/2.
  2. ButcherCapybara 👍 1 Answered C
    Eth 0/0/3 is a satically learned MAC, Correct answer is C. Frame will be forwarded through ETH 0/0/1
  3. Heidorn 👍 1 Answered C
    Correct answer is C, based on the forwarding logic

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