I used the API "_cat/indices?v" to list all indices, and I noticed that the health status of some indices were yellow. I don't understand why the health status were yellow. Could anybody please explain this? Thanks.
bash-4.2# curl http://10.99.68.208:9200/_cat/indices?v health status index uuid pri rep docs.count docs.deleted store.size pri.store.size yellow open audit-wauiynwo5urarkptmbo5-201807 d6E9b6VoS1qlZ87LeTL0EQ 5 1 100 0 108.7kb 108.7kb green open t-wauiynwo5urarkptmbo5-kibana Yxaclh2DQ7KfE946gSLYqQ 1 0 28 1 36.7kb 36.7kb