Open search index health RED

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser): OpenSearch

Describe the issue: Index health has become Red and it is not returning to yellow or green

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Hi @Abhiram - welcome to the forums! Always nice to see someone make their first post.

In regards to your question, an index going RED means that the primary shard for it is lost, and a replica hasn’t been promoted to take it’s place. It looks like the specified number of replicas for your index is 1, so there should be something being put in its place.

The first thing I’d check is the explain api for cluster shard allocation. Try hitting this URL on port 9200 for your opensearch cluster:

/_cluster/allocation/explain

If the index has gone red from, say, a lack of disk space or a node crashing, you can usually get things going again by bringing the nodes back up, or adding another node to your cluster that your index replica can be allocated to.

However, if the shard has been corrupted you can try to restore from a snapshot. If all else fails you can try to restore from a stale shard, but the results are almost certainly going to be questionable.

Let me know if I can answer any other questions. I’ll do my best.