A rrdtool network graph generator, as seen on https://mirror.kescher.at.

daemon

#!/usr/bin/env bash

while :; do
	bash loop
	sleep 5
done

loop

#!/usr/bin/env bash

rrdtool=/usr/bin/rrdtool
db0=/srv/rrdtool/eth0.rrd
img=/dev/shm/mirror-page

if [[ ! -e $db0 ]]; then
	$rrdtool create $db0 \
		-s 10 \
		DS:in:DERIVE:10:0:1250000000 \
		DS:out:DERIVE:10:0:1250000000 \
		RRA:MAX:0.5:1:360 \
		RRA:MAX:0.5:6:1440 \
		RRA:MAX:0.5:24:2520 \
		RRA:MAX:0.5:144:1800
fi

in0=$(ifconfig ens3 | grep bytes | awk '{print $5}' | sed -n '1p')
out0=$(ifconfig ens3 | grep bytes | awk '{print $5}' | sed -n '2p')

$rrdtool updatev $db0 -t in:out N:"$in0":"$out0" > /dev/null

if [[ ! -d $img ]]; then
	mkdir -p $img
fi

for period in hour
do
	$rrdtool graph $img/kalos-1$period.png -s -1$period \
		-t "kalos: Traffic last $period" \
		--lazy -l 0 -M -Y -R light \
		-c BACK#181A1B -c CANVAS#25282A -c FONT#E8E6E3 -c AXIS#E8E6E3 -c FRAME#E8E6E3 -c ARROW#E8E6E3 \
		DEF:in=$db0:in:MAX \
		DEF:out=$db0:out:MAX \
		CDEF:outei=out,8,* \
		CDEF:in_ei=in,8,* \
		"TEXTALIGN:left" \
		"COMMENT:Max         " \
		"COMMENT:Avg\\r" \
		"AREA:outei#008000:Outgoing\\l" \
		"COMMENT:\\u" \
		"GPRINT:outei:MAX:%7.1lf %Sbps" \
		"GPRINT:outei:AVERAGE:%7.1lf %Sbps\\r" \
		"LINE:in_ei#0000FFA0:Incoming\\l" \
		"COMMENT:\\u" \
		"GPRINT:in_ei:MAX:%7.1lf %Sbps" \
		"GPRINT:in_ei:AVERAGE:%7.1lf %Sbps\\r" \
	-h 102 -w 500 -l 0 -a PNG > /dev/null
done

rrdtool-network.service

[Unit]
Description=rrdtool network graph generator

[Service]
ExecStart=/usr/local/lib/rrdtool/daemon
WorkingDirectory=/usr/local/lib/rrdtool
Type=simple

[Install]
WantedBy=multi-user.target