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Diffstat (limited to 'extensions/libipt_connlimit.man')
-rw-r--r-- | extensions/libipt_connlimit.man | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/extensions/libipt_connlimit.man b/extensions/libipt_connlimit.man new file mode 100644 index 0000000..ca5974e --- /dev/null +++ b/extensions/libipt_connlimit.man @@ -0,0 +1,27 @@ +Allows you to restrict the number of parallel connections to a server per +client IP address (or client address block). +.TP +[\fB!\fR] \fB--connlimit-above \fIn\fR +Match if the number of existing connections is (not) above \fIn\fR. +.TP +\fB--connlimit-mask\fR \fIprefix_length\fR +Group hosts using the prefix length. For IPv4, this must be a number between +(including) 0 and 32. For IPv6, between 0 and 128. +.P +Examples: +.TP +# allow 2 telnet connections per client host +iptables -A INPUT -p tcp --syn --dport 23 -m connlimit --connlimit-above 2 -j REJECT +.TP +# you can also match the other way around: +iptables -A INPUT -p tcp --syn --dport 23 -m connlimit ! --connlimit-above 2 -j ACCEPT +.TP +# limit the number of parallel HTTP requests to 16 per class C sized \ +network (24 bit netmask) +iptables -p tcp --syn --dport 80 -m connlimit --connlimit-above 16 +--connlimit-mask 24 -j REJECT +.TP +# limit the number of parallel HTTP requests to 16 for the link local network \ +(ipv6) +ip6tables -p tcp --syn --dport 80 -s fe80::/64 -m connlimit --connlimit-above +16 --connlimit-mask 64 -j REJECT |