We have an ES cluster - started with 3 machines and we recently added 2 more. We are processing user aggregation data. We had an index called users-v6 and when we added the new machines it distributed across them. We wanted to rerun the aggregations so we wrote to a new index - users-v7.
The interesting part is that the v7 is only running on the initial machines and is not putting shards/replicas on the the other nodes.
The machines are supposed to be the same - though the new machines have more cores/cpus (I'm not sure if they hyperthreading, etc.. new have 4 CPUs in htop, new have 16 CPUs). The old machines have about 1TB SSD and the new about 700GB. All have 32 GB RAM, heap set to 16GB.
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