A data-center server sends frames larger than the switch port allows. The switch counts giants, while small frames pass cleanly. Which fault matches those counters?
Select an answer to reveal the explanation.
Short Explanation
The switch is refusing a truck that is too tall for the underpass, and it writes that refusal down as a giant. Your server is sending frames larger than the port allows, while small frames pass, so the MTU does not match along the path. Undersized frames, checksum failures that leave the giant counter alone, and CRC errors that are not this counter do not match the reading.
Full Explanation
A giant is a frame larger than the maximum the interface is configured to accept. The server is emitting those oversized frames, the switch counts giants, and small frames still pass, so the path is up and the failure is size. The usual cause is an MTU mismatch: the server is using a larger payload, often a jumbo payload, while the switch port is still set for the standard 1500-byte Ethernet payload. The port discards what exceeds its limit and increments the giant counter. Runts are the opposite problem, frames below the minimum legal size. A runt counter would climb on undersized frames, and small frames here are fine, so the symptom is not runts. Interference typically corrupts frames of ordinary size and shows up as CRC or input errors. Those damaged frames are not giants, and a checksum failure on a normal frame does not explain a counter that moves only when the server sends large frames. CRC errors count frames that failed the checksum. They can climb from interference, and they are not the giant counter the switch is incrementing for frames that are simply too large. Exam caveat: every device on the path has to agree. Raising the server and forgetting one switch in the middle recreates the giants on that hop. Operational check: compare the MTU on the server and on the switch port, align them, and confirm the giant counter stops increasing while a large transfer runs and small frames still succeed.