Table of Contents

Monitoring Lighttpd

When lighty has been compiled with support for rrdtool, it can generate nice graphs about it's usage (traffic, requests). The following shows how to enable this feature.

Lighttpd Config

The module mod_rrdtool has to be loaded. Then the following configuration settings need to be set: 

rrdtool.binary = "/usr/bin/rrdtool"
rrdtool.db-name = "/var/run/lighttpd/lighttpd.rrd"

Generating The Graphs

To generate graphs from the RRD database, a custom shell script has to be created: 

#!/bin/sh

RRDTOOL=/usr/bin/rrdtool
OUTDIR=/var/www/nwl.cc/htdocs-secure/lighttpd_graph/
INFILE=/var/run/lighttpd/lighttpd.rrd
OUTPRE=lighttpd-traffic
WIDTH=600
HEIGHT=350

DISP="-v bytes --title TrafficWebserver \
        DEF:binraw=$INFILE:InOctets:AVERAGE \
        DEF:binmaxraw=$INFILE:InOctets:MAX \
        DEF:binminraw=$INFILE:InOctets:MIN \
        DEF:bout=$INFILE:OutOctets:AVERAGE \
        DEF:boutmax=$INFILE:OutOctets:MAX \
        DEF:boutmin=$INFILE:OutOctets:MIN \
        CDEF:bin=binraw,-1,* \
        CDEF:binmax=binmaxraw,-1,* \
        CDEF:binmin=binminraw,-1,* \
        CDEF:binminmax=binmaxraw,binminraw,- \
        CDEF:boutminmax=boutmax,boutmin,- \
        AREA:binmin#ffffff: \
        STACK:binmax#f00000: \
        LINE1:binmin#a0a0a0: \
        LINE1:binmax#a0a0a0: \
        LINE2:bin#efb71d:incoming \
        GPRINT:bin:MIN:%.2lf \
        GPRINT:bin:AVERAGE:%.2lf \
        GPRINT:bin:MAX:%.2lf \
        AREA:boutmin#ffffff: \
        STACK:boutminmax#00f000: \
        LINE1:boutmin#a0a0a0: \
        LINE1:boutmax#a0a0a0: \
        LINE2:bout#a0a735:outgoing \
        GPRINT:bout:MIN:%.2lf \
        GPRINT:bout:AVERAGE:%.2lf \
        GPRINT:bout:MAX:%.2lf \
        "
$RRDTOOL graph $OUTDIR/$OUTPRE-hour.png -a PNG --start -14400 $DISP -w $WIDTH -h $HEIGHT
$RRDTOOL graph $OUTDIR/$OUTPRE-day.png -a PNG --start -86400 $DISP -w $WIDTH -h $HEIGHT
$RRDTOOL graph $OUTDIR/$OUTPRE-month.png -a PNG --start -2592000 $DISP -w $WIDTH -h $HEIGHT

OUTPRE=lighttpd-requests

DISP="-v req --title RequestsperSecond -u 1 \
        DEF:req=$INFILE:Requests:AVERAGE \
        DEF:reqmax=$INFILE:Requests:MAX \
        DEF:reqmin=$INFILE:Requests:MIN \
        CDEF:reqminmax=reqmax,reqmin,- \
        AREA:reqmin#ffffff: \
        STACK:reqminmax#00f000: \
        LINE1:reqmin#a0a0a0: \
        LINE1:reqmax#a0a0a0: \
        LINE2:req#00a735:requests"

$RRDTOOL graph $OUTDIR/$OUTPRE-hour.png -a PNG --start -14400 $DISP -w $WIDTH -h $HEIGHT
$RRDTOOL graph $OUTDIR/$OUTPRE-day.png -a PNG --start -86400 $DISP -w $WIDTH -h $HEIGHT
$RRDTOOL graph $OUTDIR/$OUTPRE-month.png -a PNG --start -2592000 $DISP -w $WIDTH -h $HEIGHT

To have the graphs being updated regularly, add a line to /etc/crontab: 

0,20,40 * * * * nice -n 10 /opt/lighttpd_rrdtool/gen_graphs.sh > /dev/null 2>&1

which assumes that the script given above has been saved as /opt/lighttpd_rrdtool/gen_graphs.sh and made executable.

The HTML Index File

A sample index.html could look like this: 

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
        "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title>Lighttpd traffic &amp; requests</title>
    <meta http-equiv="content-type" content="application/xhtml+xml; charset=UTF-8"/>
</head>

<body>
    <div>
        <h2>Lighttpd Traffic</h2>
        <img src="lighttpd-traffic-hour.png"   alt="graph1"><br>
        <img src="lighttpd-traffic-day.png"    alt="graph2"><br>
        <img src="lighttpd-traffic-month.png"  alt="graph3"><br>
    </div>
    <div>
        <h2>Lighttpd Requests</h2>
        <img src="lighttpd-requests-hour.png"  alt="graph4"><br>
        <img src="lighttpd-requests-day.png"   alt="graph5"><br>
        <img src="lighttpd-requests-month.png" alt="graph6"><br>
    </div>
  </body>
</html>