Let's say I set up a spot fleet with a desired count of 50 instances. Also, AWS is only able to fulfill 40 of them using spot instances, either because the spot pool is empty or because my bid price is too low. Is there something I can set up so that the other 10 get fulfilled using on-demand instances (without adding more spot pools)?
From what I understand the on_demand_base_capacity and on_demand_percentage_above_base_capacity settings for the spot fleet don't work for this, because those are not dependent on how many spot instances were actually fulfilled, only how many spot instances were requested.