Using scp with large files kills ethernet? This morning I tried to use scp to copy a single large file from my old Linux Ubuntu machine to my brand new 2017 Mac Book Pro. I ran into a very strange problem: scp would happily copy 95% of data (around 150 MB/sec) - to then "stall", and at some point tell me about broken connection. Afterwards, I basically had no more LAN access.

This happened on MacOs Sierra. What could be the reason?
Turns out: the culprit was neither the Mac itself, nor my Linux box.

I later found that the LogiLink USB-C to Ethernet adapter caused this. 

And for the record - there were various other symptoms, such as: 


download of large files in my browser being extra slow
replicating large files via IBM Notes not only being slow, but basically turning the whole machine into "almost unresponsive" mode