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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\fP \fIprefix_length\fP
+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