Dear Ryan. >> is there a way to combine iptables parameters like: iptables -A OUTPUT >> -p UDP & -p TCP -d $IP1 & -d $IP2 ? > > Each of those parameters is called a "match", in IPTables-speak. You > can specify multiple matches in one rule, but all matches are combined > with an implicit logical AND. There is no way to get a logical OR > amongst multiple matches in a single rule. If you want OR logic, you > use multiple rules. > > So, your example could not work as single rule, because no single IP > packet can be both TCP and UDP, and no single IP packet can have > multiple destination IP addresses. IPTables tries to prevent you from > creating nonsensical rules like that in most situations. > > You would have to specify the required match space across multiple > rules, maybe something like this: > > iptables -A OUTPUT -p UDP -d $IP1-j DROP > iptables -A OUTPUT -p TCP -d $IP1 -j DROP > iptables -A OUTPUT -p UDP -d $IP2 -j DROP > iptables -A OUTPUT -p TCP -d $IP2 -j DROP That's what I am doing atm. Thanks for the update. Best Regards Marcus