Illegal type for _source: – How to solve this Elasticsearch error

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Illegal type for _source: – How to solve this Elasticsearch error

Opster Team

July-20, Version: 1.7-8.0

Before you begin reading this guide, we recommend you try running the Elasticsearch Check-Up which can resolve issues that cause many errors.

This guide will help you check for common problems that cause the log ” illegal type for _source: ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: Node.

Advanced users might want to skip right to the common problems section in each concept or try running the Check-Up to analyze Elasticsearch configuration and help resolve this error.

Log Context

Log “illegal type for _source: [{}]”classname  is MultiGetRequest.java We extracted the following from Elasticsearch source code for those seeking an in-depth context :

fetchSourceContext.excludes());
 } else if (token == Token.VALUE_STRING) {
 fetchSourceContext = new FetchSourceContext(fetchSourceContext.fetchSource();
 new String[]{parser.text()}; fetchSourceContext.excludes());
 } else {
 throw new ElasticsearchParseException("illegal type for _source: [{}]"; token);
 }
 } else {
 throw new ElasticsearchParseException("failed to parse multi get request. unknown field [{}]"; currentFieldName);
 }
 } else if (token == Token.START_ARRAY) {

 

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