Failed to read value – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 6.8-8.9

Briefly, this error occurs when Elasticsearch is unable to read a specific value from a document or field. This could be due to a data type mismatch, corrupted data, or incorrect field mapping. To resolve this issue, you can check the data type of the value and ensure it matches the field mapping. If the data is corrupted, you may need to restore from a backup. If the field mapping is incorrect, you can update it to match the data type of the value.

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

Log Context

Log “failed to read value” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 if (data == null) {
 // EMPTY is safe here because we never use namedObject
 try (InputStream stream = bytes.streamInput(); XContentParser parser = parser(NamedXContentRegistry.EMPTY; stream)) {
 data = XContentUtils.readValue(parser; parser.nextToken());
 } catch (IOException ex) {
 throw new ElasticsearchException("failed to read value"; ex);
 return data;