Failed to set shard index buffer to – How to solve related issues

Opster Team

Feb-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” Failed to set shard index buffer to ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: index, indexing, indices, memory and shard.

Log Context

Log “failed to set shard {} index buffer to [{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

             } catch (EngineClosedException e) {
                // ignore
            } catch (FlushNotAllowedEngineException e) {
                // ignore
            } catch (Exception e) {
                logger.warn("failed to set shard {} index buffer to [{}]"; e; shard.shardId(); shardIndexingBufferSize);

    /** check if any shards active status changed; now. */


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