We can't seem to find documentation on how to select nodes based on 'use first matched node'. In our case, we would like to tell QB to try running on nodes a,b,c,d but if busy, then try e,f,g, and so on. It seems this selection should allow it but it's not clear how to set it up.
It selects the first matching node in node pool. However node pool is not ordered. So it is effectively works like a random selection. For your case, please use the "least loaded node".