Hi,  The Autobalance job will balance the data in the pools. So in your case, the data will be re-balanced within the pool B where you added the 3 new nodes. If there is scope for re-balance in Pool A, the job will perform that within Pool A as well. I am assuming you have set the policy to default, which is to store data anywhere.  As you mentioned there are no file-pool policies that perform data tiering, so unless Disk Pool A is filled and if the setting for Spillover is not enabled (Under SmartPool Settings), the data will stay within Pool A.  Hope this helps.  Thanks.
I currently have a rebalance running on an isilon cluster. Lets say there are node pools A and B.  -Pool A has 3 - 30 tb nodes -Pool B has 3 - 100 tb nodes. all other specs are the same. -3 nodes were added to pool B   I know the data will be restriped for Pool B, but assuming there are no policies set and they share the same protection level, will pool A send some of its files over to pool B to help get an even spread across all the nodes?  If yes, what would keep this from happening? Thanks again community!
will an isilon rebalance job work across node pools?