Char cannot be used for escaping – 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 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 ” Char cannot be used for escaping ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: parser and plugin.

Log Context

Log “Char [{}] cannot be used for escaping”classname  is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

throw new ParsingException(source(escapeCtx); "A character not a string required for escaping; found [{}]"; escapeString);
 } else if (escapeString.length() == 1) {
 escape = escapeString.charAt(0);
 // these chars already have a meaning
 if (escape == '*' || escape == '%' || escape == '_') {
 throw new ParsingException(source(escapeCtx.escape); "Char [{}] cannot be used for escaping"; escape);
 // lastly validate that escape chars (if present) are followed by special chars
 for (int i = 0; i < pattern.length(); i++) {
 char current = pattern.charAt(i);
 if (current == escape) {


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