alter munin rrds to remove artefact

Source http://it.toolbox.com/blogs/unix-sysadmin/altering-muninrrdtool-data-28015

Script fixrrd.sh

dir=$1
what=$2
cd /tmp
cp /var/lib/munin/${dir}/${what}* .
for rrd in ${what}*.rrd
do
   rrdtool dump ${rrd} | perl  -pe 's/(.*) \d\.\d+e\+1\d (<\/v>.*)/$1 0.0000000000e+00 $2/' > ${rrd}.xml
   rrdtool restore ${rrd}.xml  ${rrd}.new
   cp ${rrd}.new /var/lib/munin/${dir}/${rrd}
done
su munin -c '/usr/bin/munin-cron'

can be called as follows:

munin:~# ls /var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz*
/var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_in-c.rrd
/var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_out-c.rrd
munin:~# bash -x fixrrd.sh pokersource.info z2-7.pokersource.info-kvm_io-slitaz
+ dir=pokersource.info
+ what=z2-7.pokersource.info-kvm_io-slitaz
+ cd /tmp
+ cp /var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_read-c.rrd /var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_write-c.rrd .
+ for rrd in '${what}*.rrd'
+ rrdtool dump z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_read-c.rrd
+ perl -pe 's/(.*) \d\.\d+e\+1\d (<\/v>.*)/$1 0.0000000000e+00 $2/'
+ rrdtool restore z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_read-c.rrd.xml z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_read-c.rrd.new
+ cp z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_read-c.rrd.new /var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_read-c.rrd
+ for rrd in '${what}*.rrd'
+ rrdtool dump z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_write-c.rrd
+ perl -pe 's/(.*) \d\.\d+e\+1\d (<\/v>.*)/$1 0.0000000000e+00 $2/'
+ rrdtool restore z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_write-c.rrd.xml z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_write-c.rrd.new
+ cp z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_write-c.rrd.new /var/lib/munin/pokersource.info/z2-7.pokersource.info-kvm_io-slitaz_fsffrance_vm_gnt_write-c.rrd
+ su munin -c /usr/bin/munin-cron