i think that i have forgot to say something important, let me show with a picture.
This is the original scenario without ZS, a simple classic network:
and this is the scenario wanted:
all fine, lan clients can use internet, but all fine except the continuosly strange traffic between ETH00 and ETH01 in my Sun’s VirtualBox doing nothing. This causes a slowly internet access in the lan clients
peharps this pictures will show the problem in my network