This field reports the cumulative count of FCoE frames that failed to be transmitted correctly out this interface, tracked by this particular stats object since it was created or last reset. For a network admin, this is the transmit-side counterpart to errorsRx, and a steady climb suggests an adapter or fabric-interconnect-side problem originating from this blade rather than from the far end. For example, a cumulative value of 16 frames since the interface came up would still be within a tolerable range, whereas a rapidly climbing count in the hundreds would justify escalation.