Why does Shorewall lPv6 Support Require Kernel 2.6.24 or later?
Shorewall implements a stateful firewall which requires connection tracking be present in ip6tables and in the kernel. Linux kernels before 2.6.20 didn’t support connection tracking for IPv6. So we could not even start to develop Shorewall IPv6 support until 2.6.20 and there were significant problems with the facility until at least kernel 2.6.23. When distributions began offering IPv6 connection tracking support, it was with kernel 2.6.25. So that is what we developed IPv6 support on and that’s all that we initially tested on. Subsequently, we have tested Shorewall6 on Ubuntu Hardy with kernel 2.6.24. If you are running 2.6.20 or later, you can try to run Shorewall6 by hacking /usr/share/shorewall/prog.footer6 and changing the kernel version test to check for your kernel version rather than 2.6.24 (20624). But after that, you are on your own.
