title: Elasticsearch Unassigned Shard: How to reassign back?
body: <p>We have 3 data node cluster and all our indices have 1 primary + 2 replica shards on each index. All the indices were running properly with a green status for the cluster until a couple of days ago.</p>
  <p>For some reason, only one of the indices now has a yellow status with 1 unassigned index error. When I run <code>_cluster/allocation/explain</code>, it tells me that &quot;the shard cannot be allocated to the same node on which a copy of the shard already exists&quot;. If I look at the cluster health on Kibana, I don't see a duplicate shard on that node.</p>
  <p><a href="https://i.stack.imgur.com/g6I54.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/g6I54.png" alt="enter image description here" /></a></p>
  <p>So I am not quite sure what the problem is. Can someone offer any advice on this?</p>