Batch processing thorugh multiple AOS instances in AX2012

Hi,

I am actually trying to import Sales order through excel using batch processing.

In my scenario i would be running batch process from one system but is should generate multiple tasks which should run on multiple AOS instances.

 I have configured 2 AOS instance on my system (on which batch is running) but tasks are not getting divided on multiple AOS even though batch group is created with 2 AOS.

Can anybody guide on same?

Regards, Rahul