Good morning With iptables in CentOS 5 and 6 Linux - how can you please prevent processes running as "root", "apache" or "nobody" from initiating outgoing connections? On CentOS 5 Linux I've tried putting these lines into /etc/sysconfig/iptables: -A OUTPUT -m owner --uid-owner root -j DROP -A OUTPUT -m owner --uid-owner apache -j DROP -A OUTPUT -m owner --uid-owner nobody -j DROP but unfortunately get the error: # sudo service iptables restart iptables: Flushing firewall rules: [ OK ] iptables: Setting chains to policy ACCEPT: filter [ OK ] iptables: Unloading modules: [ OK ] iptables: Applying firewall rules: iptables-restore v1.4.7: owner: Bad value for "--uid-owner" option: "apache" Error occurred at line: 27 Try `iptables-restore -h' or 'iptables-restore --help' for more information. [FAILED] Thank you Alex