It seems that changes in 4.5 collection configuration now require users to set a maxShardsPerNode (or it defaults to 1).
Maybe this was the case before, but with the new CREATESHARD API it seems a very restrictive. I've just created a very simple test collection on 3 machines where I set maxShardsPerNode at collection creation time to 1, and I made 3 shards. Everything is good. Now I want a 4th shard, it seems impossible to create because the cluster "knows" I should only have 1 shard per node. Yet my problem doesn't require more hardware, I just my new shard to exist on one of the existing servers. So I try again -- I create a collection with 3 shards and set maxShardsPerNode to 1000 (just as a silly test). Everything is good. Now I add shard4 and it immediately tries to add 1000 replicas of shard4... You can see my earlier email today about time-oriented data in 4.5 to see what I'm trying to do. I was hoping to have 1 shard per hour/day with the ability to easily add/drop them as I move the time window (say, a week of data, 1 per day). Am I missing something? Thanks!
