Open a support case with a Discovery Diag and they can help. Give them 2 examples a device where it's work and one where it's not. Also, include Code version and Model( I like to use the same models if that is possible) https://support.infoblox.com
The .* in regex will include end of line. Try using .+ instead. I am assuming you don't want any match on the first line. http://www.tutorialspoint.com/ruby/ is a pretty good resource. Let us know if this works, I didn't try it.