Greetingz!
I'm going to break my personal rule about responding to Ubuntu-based posts (as I don't use that particular distribution enough...)
Looking at the first problem....Ubuntu + NTFS on a RAID5 via USB3...and it dies 2 to 3 gb into a 6gb file copy. I'm honestly surprized it *worked*.
I'm willing to bet if you ran '
time cp -rv' instead of just plain old '
cp -rv' that you'd find the command taking the exact same amount of time to die each time you ran it.
However, when looking at the second problem, things start to make sense. It appears that the RAID array is going to sleep (standby)...
This might help.