This field reports the cumulative count of CRC (cyclic redundancy check) errors — frames whose checksum did not match their contents, meaning the frame was corrupted somewhere on the wire, tracked by this particular stats object since it was created or last reset. For a network admin, on this network-interface error table, a climbing CRC count is the classic signature of a bad cable, a failing SFP, or electrical noise on the link, and is usually the first counter an admin checks when a NIC reports flakiness. For example, a cumulative value of 36 CRC errors since the interface came up would still be within a tolerable range, whereas a rapidly climbing count in the hundreds would justify escalation.