iostat graph help

Hi. I am new to Hobbit, but so far it is an amazing tool. I have been trying to figure out how to add iostat graphs to the trends column, but I have had no luck. I was hoping someone already knows how to do this. I see that iostat already has a graph configuration ready to use, but I'm not sure how to generate the rrd file. Is there a way to graph iostat? Thank you for your help.

Regards,

Bryan Kennedy