Also if I know I have a node I want to take down - can I force all the primaries to migrate to other machines before hand to minimize any effect. This become more crucial when sometimes we have indices without replication (either because of size constraints or ingestion performance - the use case can tolerate failure/restarting.) Even though we can reindex if we need to - if we know we want to take a machine down - we would like to migrate all the primary/singular indices off that node to avoid needless downtime.
I see from https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-reroute.html that I can reroute specific shard - but then the cluster will rebalance. It seems I can mitigate this - but I'm not sure how much. Further - I would like to do this globally for all shards on this node - not for individual shards.
Is this possible?