Talk:Simple stateful firewall
Clarification on syn scan rules
Maybe I misunderstood some of the instructions but I found that I needed to insert the rules into the chains TCP and UDP rather than OPEN-TCP and OPEN-UDP as the latter didn't exist:
# iptables -I TCP -p tcp -m recent --update --seconds 60 --name TCP-PORTSCAN -j REJECT --reject-with tcp-rst # iptables -I UDP -p udp -m recent --update --seconds 60 --name UDP-PORTSCAN -j REJECT --reject-with port-unreach
I also found that I needed to add an --update:
# iptables -A INPUT -p icmp --icmp-type echo-request -m recent --name ping_limiter --hitcount 6 --seconds 4 -j DROP
I believe an --rcheck would also have worked. I'm not sure which would be correct. In general, I found this very helpful in conjunction with the man page for iptables. --Margali 21:57, 29 December 2011 (EST)
- I just checked, the above suggestions are in the rules now. closing --Indigo (talk) 21:45, 11 September 2013 (UTC)
IPv6 icmp replies
For ipv6 adaptation. As --reject-with icmp6-proto-unreachable does not exist in ipv6, as told in the page, and according to the error messages description in the RFC []. I think the icmp6-adm-prohibited which means "Communication with destination administratively prohibited" may be the message to send. It is only by reading the RFC, I am not a network expert and I have no idea of what is generally done in this case.--Cladmi 07:28, 15 February 2012 (EST)
References to OPEN chain(s)
I've re-read the guide once again and noticed multiple references to a now non-existent OPEN chain. A few years ago the OPEN chain was split into OPEN-TCP and OPEN-UDP, now simply TCP and UDP. See the relevant edits: , .
There are two solutions, either drop the references to the OPEN chain(s) completely, or undo those very old edits. If there are no objections, I'll go with the former.