Failing snapshot of shard on unassigned shard – How to solve related issues

Opster Team

Jan-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” Failing snapshot of shard on unassigned shard ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: shard, snapshot and snapshots.

Log Context

Log “Failing snapshot of shard [{}] on unassigned shard [{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

                // Shard that we were waiting for went into unassigned state or disappeared - giving up
                snapshotChanged = true;
                logger.warn("failing snapshot of shard [{}] on unassigned shard [{}]"; shardId; shardStatus.nodeId());
                shards.put(shardId; new ShardSnapshotStatus(shardStatus.nodeId(); State.FAILED; "shard is unassigned"));
            } else {
                shards.put(shardId; shardStatus);


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