Op 27/04/2011 om 13:22:57 +0200, schreef Jan Engelhardt: > On Wednesday 2011-04-27 12:43, Ulrich Weber wrote: > > >Each fragmented IPv6 packets will traverse netfilter separately, > >in contrast to IPv4, where its only one refragmented packet. > > Not really. All fragments enter nf_hook_slow, be it IPv4 or IPv6. > It's just that nf_defrag - which is a netfilter module - collects and > suppresses fragments before spitting out the unfragmented one. > > >"ip6tables -A INPUT -j ACCEPT -p udp --dport 53" will only match the > >first fragment, where the UDP header can be found. To match the > >additional fragments, you have to insert these rules: > > > >ip6tables -I INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT > >ip6tables -I OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT > > That will load nf_conntrack_ipv6, and because conntrack depends on > nf_defrag_ipv6, will load that too. Once it is loaded, packets should > be defragmented independetly of whether you actually use -m conntrack > (or the obsolete -m state) or not. my /proc/config.gs says: CONFIG_NF_CONNTRACK_IPV6=y so it is already loaded But is does not defrag. Also I am a bit worried about using conntrack because of the high volume dns queries tend to be which would generate a very large connectiontracking table and/or system load. -- Leo Baltus, internetbeheerder /\ NPO ICT Internet Services /NPO/\ Sumatralaan 45, 1217 GP Hilversum, Filmcentrum, west \ /\/ beheer@xxxxxxxxx, 035-6773555 \/ -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
