1This creates an LED-trigger that can then be attached to system indicator 2lights, to blink or illuminate them when certain packets pass through the 3system. One example might be to light up an LED for a few minutes every time 4an SSH connection is made to the local machine. The following options control 5the trigger behavior: 6.TP 7\fB\-\-led\-trigger\-id\fP \fIname\fP 8This is the name given to the LED trigger. The actual name of the trigger 9will be prefixed with "netfilter-". 10.TP 11\fB\-\-led-delay\fP \fIms\fP 12This indicates how long (in milliseconds) the LED should be left illuminated 13when a packet arrives before being switched off again. The default is 0 14(blink as fast as possible.) The special value \fIinf\fP can be given to 15leave the LED on permanently once activated. (In this case the trigger will 16need to be manually detached and reattached to the LED device to switch it 17off again.) 18.TP 19\fB\-\-led\-always\-blink\fP 20Always make the LED blink on packet arrival, even if the LED is already on. 21This allows notification of new packets even with long delay values (which 22otherwise would result in a silent prolonging of the delay time.) 23.TP 24Example: 25.TP 26Create an LED trigger for incoming SSH traffic: 27iptables \-A INPUT \-p tcp \-\-dport 22 \-j LED \-\-led\-trigger\-id ssh 28.TP 29Then attach the new trigger to an LED: 30echo netfilter\-ssh >/sys/class/leds/\fIledname\fP/trigger 31