Dear all, I am experimenting with altering the TCP MSS using iptables/ip6tables v1.2.5 under Linux 2.4.18 I am able to do that for IPv4 traffic using the options e.g. iptables -A OUTPUT -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --set-mss 1000 iptables -A OUTPUT -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu This is, as expected, applied to IPv4 traffic. I need to do something equivalent (being able to manually alter MSS) for IPv6, but the TCPMSS option does not seem to work for ip6tables. ------------------------------------------------------------------------ ----- # ip6tables -A OUTPUT -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --set-mss 1400 ip6tables v1.2.5: Unknown arg `--set-mss' Try `ip6tables -h' or 'ip6tables --help' for more information. ------------------------------------------------------------------------ ----- Am I doing something obviously wrong, or such functionality is not (yet) implemented for ip6tables? Or even, is there a specific patch that I need to apply? Many thanks for any help, Dimitris.
