elasticsearch - All shards failed

Question

I was working on elastic search and it was working perfectly. Today I just restarted my remote server (Ubuntu). Now I am searching in my indexes, it is giving me this error.

{"error":"SearchPhaseExecutionException[Failed to execute phase [query_fetch], all shards failed]","status":503}

I also checked the health. The status is red. Can anyone tell me what's the issue.

Answer 1

It is possible on your restart some shards were not recovered, causing the cluster to stay red.
If you hit:
http://<yourhost>:9200/_cluster/health/?level=shards you can look for red shards.

I have had issues on restart where shards end up in a non recoverable state. My solution was to simply delete that index completely. That is not an ideal solution for everyone.

It is also nice to visualize issues like this with a plugin like:
Elasticsearch Head