#1) What are you trying to accomplish? I've seen you throw a half dozen tools around this thread, all of which have specific (and different) uses.

#2) If you are trying to simply arp spoof and you can't get things working, there is yet another unix based tool called frag router that you may want to play with. The folks at (what used to be) Foundstone were big pushers of this little utility. Anyway, this is for your arp poisoning adventure.

#3) Ettercap comes with a bunch of canned tools that allow you to do arp poisoning, password logging, DoS attacks, etc., etc.. This is an "one stop shop" solution for the skiddie in all of us. Since you seem interested in doing a lot of things at once, this may be your best bet.

#4) Piping to dev/null isn't a solve all solution for output. There are cases where you will have to specifically state not to drop content to the terminal.

--TH13