A client who over grew the capacity of their Dual Opteron server planned on moving their site to a 2X Quad Xeon machine.

One of the things we use on the server is Munin for resource utilization and statistics. It is a server side tool that can monitor CPU, Memory, network, Apache, MySQL and much more. It has a web based interface that generates graphs from RRD Tool files.

In order not to lose the history, I copied the /etc/munin and /var/lib/munin from the old machine to the new one. However, after copying them, the graphs were not updating. After some investigation, the logs were showing the following error:

Unable to graph /var/lib/munin/.../processes-processes-g.rrd: This RRD was created on other architecture

So, it was aparent that the file structure is CPU dependent.

However, the nice thing about RRD Tool is that it has built in support for export/import to/from an XML format.

Hence I was able to do this on the source machine:

for FILE in *rrd
do 
rrdtool dump $FILE > $FILE.xml
done 

Generating one .xml file for each .rrd file.

Then on the new machine, I did this:

for FILE in *xml
do 
NEW=`basename $FILE .xml`
rrdtool restore $FILE $NEW
done 

Voila ...

The error message disappeared and the graphs showed the old history correctly.