Iptables; Additional Resources - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

For more information about IPv6 networking, refer to the IPv6 Information Page at
www.ipv6.org/.

43.8.9. Additional Resources

There are several aspects to firewalls and the Linux Netfilter subsystem that could not be covered in
this chapter. For more information, refer to the following resources.
43.8.9.1. Installed Documentation
Section 43.9, "IPTables"
• Refer to
including definitions for many command options.
• The iptables man page contains a brief summary of the various options.
43.8.9.2. Useful Websites
http://www.netfilter.org/
•
http://www.tldp.org/
• — The Linux Documentation Project contains several useful guides relating to
firewall creation and administration.
http://www.iana.org/assignments/port-numbers
•
ports as assigned by the Internet Assigned Numbers Authority.
43.8.9.3. Related Documentation
• Red Hat Linux Firewalls, by Bill McCarty; Red Hat Press — a comprehensive reference to building
network and server firewalls using open source packet filtering technology such as Netfilter and
iptables. It includes topics that cover analyzing firewall logs, developing firewall rules, and
customizing your firewall using various graphical tools.
• Linux Firewalls, by Robert Ziegler; New Riders Press — contains a wealth of information on building
firewalls using both 2.2 kernel ipchains as well as Netfilter and iptables. Additional security
topics such as remote access issues and intrusion detection systems are also covered.

43.9. IPTables

Included with Red Hat Enterprise Linux are advanced tools for network packet filtering — the process
of controlling network packets as they enter, move through, and exit the network stack within the
kernel. Kernel versions prior to 2.4 relied on ipchains for packet filtering and used lists of rules
applied to packets at each step of the filtering process. The 2.4 kernel introduced iptables (also
called netfilter), which is similar to ipchains but greatly expands the scope and control available for
filtering network packets.
This chapter focuses on packet filtering basics, defines the differences between ipchains and
iptables, explains various options available with iptables commands, and explains how filtering
rules can be preserved between system reboots.
Section 43.9.7, "Additional Resources"
Refer to
and setting up a firewall based on these rules.
for more detailed information on the iptables command,
— The official homepage of the Netfilter and iptables project.
for instructions on how to construct iptables rules
— The official list of registered and common service
Additional Resources
http://
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