Merge commit 'origin/trunk@12184' into fedora

[iptables.git] / trunk / extensions / libxt_connlimit.man

diff --git a/trunk/extensions/libxt_connlimit.man b/trunk/extensions/libxt_connlimit.man
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+Allows you to restrict the number of parallel connections to a server per
+client IP address (or client address block).
+.TP
+[\fB!\fP] \fB--connlimit-above\fP \fIn\fP
+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