Unexpected parameter – 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.

Briefly, this error message indicates that Elasticsearch received a request with an unexpected parameter. Elasticsearch has a well-defined API, and it expects specific parameters for each API call. This error can occur if a parameter is misspelled or if an unsupported parameter is used. To resolve this issue, you should carefully review the Elasticsearch documentation for the API you are using and ensure that you are using the correct parameters. You should also ensure that you are using the correct spelling and syntax for each parameter.

To easily locate the root cause and resolve this issue try AutoOps for Elasticsearch & OpenSearch. It diagnoses problems by analyzing hundreds of metrics collected by a lightweight agent and offers guidance for resolving them.

This guide will help you check for common problems that cause the log ” Unexpected parameter ” 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 “Unexpected parameter”classname  is ExpressionBuilder.java We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 Token token = node.getSymbol(); 
 if (params.containsKey(token) == false) {
 throw new ParsingException(source(node); "Unexpected parameter");
 return params.get(token);


See how you can use AutoOps to resolve issues

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?

Analyze your cluster & get personalized recommendations

Skip to content