On 2014-05-24 17:09, Jean-Yves Bernier wrote: At 4:15 PM +0200 24/5/14, Johnny Billquist wrote: Do I need to spell it out? :-) That was welcome :) Sorry if it came across a little brusque. Anyway... So "Physical" is not "Hardware", and there is no need to SET XQ MAC. I tried and it maked no change. Right. Since your machine will set a different MAC address anyway, at start, when you enable DECnet. The physical address is whatever you set in simh before starting. It have no actual relevance once DECnet starts. If you were to run something else, which did not use DECnet (such as Unix), the address you set in simh will be the actual MAC address used, since IP do not change the MAC address of interfaces. No need. However, that does not explain my erratic file transfers : Right. Erratic file transfers is something else, and unrelated. @TNET.CMD NFT SNAKE/SYSTEM/PASSWD::DR0:[100,100]/NV=DR0:[100,100]SINUS.SON;1 TIME 04:00:24 30-MAR-1982 NFT SNAKE/SYSTEM/PASSWD::DR0:[100,100]/NV=DR0:[100,100]SINUS.SON;1 TIME 04:04:06 30-MAR-1982 NFT SNAKE/SYSTEM/PASSWD::DR0:[100,100]/NV=DR0:[100,100]SINUS.SON;1 TIME 04:09:45 30-MAR-1982 NFT SNAKE/SYSTEM/PASSWD::DR0:[100,100]/NV=DR0:[100,100]SINUS.SON;1 TIME 04:09:47 30-MAR-1982 NFT SNAKE/SYSTEM/PASSWD::DR0:[100,100]/NV=DR0:[100,100]SINUS.SON;1 TIME 04:10:48 30-MAR-1982 NFT SNAKE/SYSTEM/PASSWD::DR0:[100,100]/NV=DR0:[100,100]SINUS.SON;1 TIME 04:12:28 30-MAR-1982