If the iptables-ipv6 package is installed, netfilter in Red Hat Enterprise Linux can filter the next-generation IPv6 Internet protocol. The command used to manipulate the IPv6 netfilter is ip6tables.

Most directives for this command are identical to those used for iptables, except the nat table is not yet supported. This means that it is not yet possible to perform IPv6 network address translation tasks, such as masquerading and port forwarding.

Rules for ip6tables are saved in the /etc/sysconfig/ip6tables file. Previous rules saved by the ip6tables initscripts are saved in the /etc/sysconfig/ip6tables.save file.

Configuration options for the ip6tables init script are stored in /etc/sysconfig/ip6tables-config, and the names for each directive vary slightly from their iptables counterparts.

For example, the iptables-config directive IPTABLES_MODULES:the equivalent in the ip6tables-config file is IP6TABLES_MODULES.