How To Solve Issues Related to Log – Rerouting shards:

How To Solve Issues Related to Log – Rerouting shards:

Updated: Jan-20

Elasticsearch Version: 1.7-8.0


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To troubleshoot log “Rerouting shards:” it’s important to understand a few problems related to Elasticsearch concepts allocation, cluster, monitor, routing, threshold. See bellow important tips and explanations on these concepts

Log Context

Log”Rerouting shards: [{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

            if (reroute) {
      "rerouting shards: [{}]"; explanation);
            indicesToMarkReadOnly.removeIf(index -> state.getBlocks().indexBlocked(ClusterBlockLevel.WRITE; index));
            if (indicesToMarkReadOnly.isEmpty() == false) {

Related issues to this log

We have gathered selected Q&A from the community and issues from Github, that can help fix related issues please review the following for further information :

1 ElasticSearch: Unassigned Shards, how to fix?

203.11 K 152

Rerouting Shards In Cluster  

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