Hi Björn and Patrik,

Thank you very much for the insight. Got a couple more follow up questions:

1. Does the akka.cluster.min-nr-of-members configuration apply to the 
cluster only when it is first started up or does it continue to stay in 
effect throughout the cluster's life cycle? The reason I ask is because I'm 
wondering if it could be used to prevent single nodes that have been 
auto-downed from starting back up again and forming separate clusters due 
to the fact that they wouldn't have the minimum number of nodes required 
for this to happen.

2. Eventually, I want to run an elastic Akka cluster that can change based 
on the load. In the documentation it says that as a rule of thumb the 
number of shards in a cluster should be a factor of ten greater than the 
planned maximum number of nodes. The issue here is that this maximum number 
of nodes could change dramatically which would make initial calculations 
for the number of shards inaccurate and would most likely degrade 
performance or at least not take full advantage of new resources. 

a. Is there any way of dynamically changing the total number of shards in a 
cluster through the ShardRegion.MessageExtractor that is used by the 
ShardRegions so that it can adapt to changes in the cluster's size?
 
b. Are there any downsides of overestimating the total number of shards 
that are going to be in a cluster in order to account for any unforeseen 
growth of the cluster? Initially I'm thinking that there will probably be 
many shards with single (or very few) entries assigned to each one although 
I figure that something like a LeastShardAllocationStrategy would be 
effective at re-balancing the load in this scenario. Also, since a "shard" 
is really an abstract concept that is actually managed by a ShardRegion (at 
least by my understanding), if I started out with a small number of nodes 
in my cluster, these nodes wouldn't really get overloaded with a bunch of 
instances of these "shards" since entries are created as children of the 
ShardRegions and there is only one ShardRegion per entry type per node.

Luis

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