I use kopf for visualization, and I tried changing the number of replica setting for an index from 17 to 20, making the replication group of 21 using kopf. (total 20 primary shards + 3 availability zones)
The observation is, it assigns some number of replica's (mainly group of 60) but others stay unassigned. Any pointers on debugging this issue ?
Elasticsearch version 1.7

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