libxt_LED.man

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:
.TP
\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-".
.TP
\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.)
.TP
\fB\-\-led\-always\-blink\fP
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.)
.TP
Example:
.TP
Create an LED trigger for incoming SSH traffic:
iptables \-A INPUT \-p tcp \-\-dport 22 \-j LED \-\-led\-trigger\-id ssh
.TP
Then attach the new trigger to an LED:
echo netfilter\-ssh >/sys/class/leds/\fIledname\fP/trigger