Error building fetch sub-phases – How to solve this Elasticsearch error

Opster Team

March-22, Version: 1.7-8.0

Before you begin reading this guide, we recommend you try running the Elasticsearch Error Check-Up which analyzes 2 JSON files to detect many configuration errors.

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This guide will help you check for common problems that cause the log ” Error building fetch sub-phases ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: search.

Log Context

Log “Error building fetch sub-phases”classname  is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

processors.add(profiler.profile(fsp.getClass().getSimpleName(); ""; processor));
 return processors;
 } catch (Exception e) {
 throw new FetchPhaseExecutionException(target; "Error building fetch sub-phases"; e);
 static class DocIdToIndex implements Comparable {
 final int docId;


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