find out what programm wants to open a ssh session?

[robert rottermann]

Hi there,
on my Ubuntu 13.04 laptop I deleted all entries in .ssh/known_hosts.
Since then, every couple of minutes I am asked that one of my remote 
hosts is not in known_hosts and whether it is OK to connect to it.

Now I wonder what process would try to open a connection to that 
particular host.

How can I find out what process that would be?

thanks for your help.
robert