Copy to in multi fields is not allowed Found the copy to in field name – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 6.8-7.1

Before you dig into reading this guide, have you tried asking OpsGPT what this log means? You’ll receive a customized analysis of your log.

Try OpsGPT now for step-by-step guidance and tailored insights into your Elasticsearch operation.

Briefly, this error occurs when the “copy_to” parameter is used within a multi-field in Elasticsearch. This is not allowed because multi-fields are meant to provide different ways of analyzing a single field, not to copy data. To resolve this issue, you can remove the “copy_to” parameter from the multi-field. Alternatively, you can create a separate field outside of the multi-field and use the “copy_to” parameter there.

For a complete solution to your to your search operation, try for free AutoOps for Elasticsearch & OpenSearch . With AutoOps and Opster’s proactive support, you don’t have to worry about your search operation – we take charge of it. Get improved performance & stability with less hardware.

This guide will help you check for common problems that cause the log ” copy_to in multi fields is not allowed. Found the copy_to in field [” + name + “] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: index.

Log Context

Log “copy_to in multi fields is not allowed. Found the copy_to in field [” + name + “] ” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 } else if (parseMultiField(builder::addMultiField; name; parserContext; propName; propNode)) {
 } else if (propName.equals("copy_to")) {
 if (parserContext.isWithinMultiField()) {
 throw new MapperParsingException("copy_to in multi fields is not allowed. Found the copy_to in field [" + name + "] " +
 "which is within a multi field.");
 } else {
 List copyFields = parseCopyFields(propNode);
 FieldMapper.CopyTo.Builder cpBuilder = new FieldMapper.CopyTo.Builder();


How helpful was this guide?

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Get expert answers on Elasticsearch/OpenSearch