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+This creates an LED-trigger that can then be attached to system indicator
+lights, to blink or illuminate them when certain packets pass through the
+system. One example might be to light up an LED for a few minutes every time
+an SSH connection is made to the local machine. The following options control
+the trigger behavior:
+\fB--led-trigger-id\fP \fIname\fP
+This is the name given to the LED trigger. The actual name of the trigger
+will be prefixed with "netfilter-".
+\fB--led-delay\fP \fIms\fP
+This indicates how long (in milliseconds) the LED should be left illuminated
+when a packet arrives before being switched off again. The default is 0
+(blink as fast as possible.) The special value \fIinf\fP can be given to
+leave the LED on permanently once activated. (In this case the trigger will
+need to be manually detached and reattached to the LED device to switch it
+off again.)
+Always make the LED blink on packet arrival, even if the LED is already on.
+This allows notification of new packets even with long delay values (which
+otherwise would result in a silent prolonging of the delay time.)
+Create an LED trigger for incoming SSH traffic:
+iptables -A INPUT -p tcp --dport 22 -j LED --led-trigger-id ssh
+Then attach the new trigger to an LED:
+echo netfilter-ssh >/sys/class/leds/\fIledname\fP/trigger