Please don't ask in random communities unrelated to the topic of question.
Use blue [ EDIT ] button on top to move this thread to LAN, Switching and Routing
By the way, I know nothing about C6506, even I don't know what kind of device it is, but the meaning of such message is clear - there has underflow occurred during packet transmission. E.g. NIC has started packet transmission into wire (or fiber or so), but the engine failed to supply data fast enough, thus transfer has been terminated prematurely.
Events like this one should not occur, or should be really very rare. It may be symptom of overloaded machine. Move the thread to appropriate community, experts more familiar with C6506 will give you better advice.
