Thumbnail Your RRDtool Graphs

If you have lots of RRDtool graphs you need to go through everyday, you may want to consider creating thumbnail dynamically from the RRD files. As CPU and memory utilisations are plotted with same scale (100%), we can put them together for ease of viewing and analysis.

A simple CGI script is able to do the job. Basically it ignores x- & y-grids/ticks/labels and legends

echo "Content-tyep: image/png"
echo ""
/usr/bin/rrdtool graph - \
        --start -${2:-1d} \
        --imgformat PNG \
        --lower-limit 0 --upper-limit 100 --rigid \
        --width=125 --height=30 \
        --x-grid none \
        --y-grid none \
        --title "$host" \
        --color=BACK#ffffff \
        --color=CANVAS#ffeee5 \
        --color=GRID#7F7F7F \
        --color=MGRID#B8B8B8 \
        --color=ARROW#FF0000 \
        DEF:usr=$rrd_cpu:usr:AVERAGE \
        DEF:sys=$rrd_cpu:sys:AVERAGE \
        DEF:wio=$rrd_cpu:wio:AVERAGE \
        DEF:idle=$rrd_cpu:idle:AVERAGE \
        DEF:mtotal=$rrd_mem:total:AVERAGE \
        DEF:mused=$rrd_mem:used:AVERAGE \
        CDEF:gbtotal=mtotal,1024,/ \
        CDEF:gbused=mused,1024,/ \
        CDEF:gbfree=mtotal,mused,-,1024,/ \
        CDEF:percent=gbfree,gbtotal,/,100,* \
        AREA:usr#dddd00:\
        STACK:sys#dd0000:\
        STACK:wio#ff8a60:\
        STACK:idle#e2e2f2:\
        LINE1:percent#0000ff: \
        GPRINT:gbfree:LAST:"Mem\:%5.1lf/" \
        GPRINT:gbtotal:LAST:"%5.1lfGB"