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8.74. iptables

Updated iptables packages that fix several bugs and add two enhancements are now available for Red Hat Enterprise Linux 6.
The iptables utility controls the network packet filtering code in the Linux kernel. The utility allows users to perform certain operations such as setting up firewalls or IP masquerading.

Bug Fixes

A previous version of iptables added the "alternatives" functionality support for the /lib/xtables/ or /lib64/xtables/ directory. However, iptables failed to replace the directory with the alternatives slave symbolic link when upgrading iptables with the "yum upgrade" command and the directory contained custom plug-in files. Consequently, some iptables modules became unavailable. This problem has been fixed by modifying the iptables spec file so that the /lib/xtables/ or /lib64/xtables/ directory is no longer managed by "alternatives".
The iptables-save command previously supported only the "--modprobe=" option to specify the path to the modprobe executable. However, the iptables-save(8) man page incorrectly stated that this action could have been performed using an unsupported option, "-M", which could lead to confusion. The iptables-save command has been modified to support the "-M" option for specifying the path to modprobe, and corrects the iptables-save(8) man page, which now correctly mentions both the "-M" and "--modprobe=" option.
Due to a bug in the iptables init script, the system could become unresponsive during shutdown when using the network-based root device and the default filter for INPUT or OUTPUT policy was DROP. This problem has been fixed by setting the default chain policy to ACCEPT before flushing the iptables rules and deleting the iptables chains.


The iptables utility has been modified to support a new option, "--queue-bypass", which allows bypassing an NFQUEUE rule if the specified queue is not used.
A new iptables service option,"reload", has been added to enable a refresh of the firewall rules without unloading netfilter kernel modules and a possible drop of connections.
Users of iptables are advised to upgrade to these updated packages, which fix these bugs and add these enhancements.