Think about the case where you want to have 3 replicas of an index, but only 2 are available (as one of your nodes broke down). Do you want HSEARCH to do its thing (all requests can be satisfied, only the replication rules are not satisfied) or not? I.e. do you want HSEARCH to send writes to the index also if the replica count currently is not what you want, or do you want to be extra safe and wait for the full number of replicas. To distinguish these two, a setting in HSEARCH would make sense.

I feel, working with yellow is good in most cases, esp. since the cluster can degrade from green to yellow any time at runtime, and we won't check or detect this after start-up. So I suggest to just change it so we only wait for yellow (log a warning if it's not green), and if there is user demand, we can still make it configurable down the road. But then we'd also have to think about what to do about degredation at runtime, i.e. should we regularly check and log errors then?

Thoughts?