Start object expected index indexName – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 6.8-7.9

Briefly, this error occurs when Elasticsearch expects a start object in the JSON request body but doesn’t find one. This is usually due to incorrect JSON formatting or syntax. To resolve this issue, you can: 1) Check the JSON request body for any syntax errors or missing brackets. 2) Validate your JSON using a JSON validator tool. 3) Ensure that the JSON request body starts with a ‘{‘ (start object) and ends with a ‘}’ (end object).

This guide will help you check for common problems that cause the log ” start object expected index[” + indexName + “] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: repositories, index.

Log Context

Log “start object expected index[” + indexName + “]” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 final List snapshotIds = new ArrayList<>();
 final List gens = new ArrayList<>();  IndexId indexId = null;
 if (parser.nextToken() != XContentParser.Token.START_OBJECT) {
 throw new ElasticsearchParseException("start object expected index[" + indexName + "]");
 while (parser.nextToken() != XContentParser.Token.END_OBJECT) {
 final String indexMetaFieldName = parser.currentName();
 if (INDEX_ID.equals(indexMetaFieldName)) {