Fix issue handling broken pipe and ssh process dead

While I'm here add back one dd to the pipe. According to Xin they are
used to couple I/O intensive, CPU intensive and network I/O (tends to
block) processes so that they can do more stuff with less blocking on
pipewr.
I'm assuming the pipe in python does the job of the first dd.

Ticket:	#4600
(cherry picked from commit 076d8710316da86f0255946fd0e139ac425c1cef)