Arno's IPTABLES Firewall Script is a secure stateful firewall for both single and multi-homed machines. It supports NAT and SNAT, port forwarding, ADSL ethernet modems with both static and dynamically assigned IPs, MAC address filtering, stealth port scan detection, DMZ support, protection against SYN/ICMP flooding, experimental IPv6 support, multi-interface/aliased-IP support, and extensive user definable logging with rate limiting to prevent log flooding. It has plugin support to add extra features (like SSH Brute Force protection and (Racoon) IPSEC support). It is easy to configure and highly customizable. A filter script that makes your firewall log more readable is also included.License: GNU General Public License v2Changes:
The $LOCAL_CONFIG_FILE variable was added toallow, for example, certain user/global/localsettings to be sourced into the script. The plugincode was moved from custom rules into the mainscript. The plugin system was enhanced. Severalplugins were updated. Multiroute now has a properstop() section. /proc/.../ conntrack set was fixedfor newer kernels.

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