Unknown field – How to solve this Elasticsearch error

Unknown field – 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 can resolve issues that cause many errors.

This guide will help you check for common problems that cause the log ” unknown field ” to appear. It’s important to understand the issues related to the log, so to get started, read the general overview on common issues and tips related to the Elasticsearch concepts: query and index.

Advanced users might want to skip right to the common problems section in each concept or try running the Check-Up which analyses ES to pinpoint the cause of many errors and provides suitable actionable recommendations how to resolve them (free tool that requires no installation).

Log Context

Log”unknown field [{}]”classname  is DecayFunctionBuilder.java We extracted the following from Elasticsearch source code for those seeking an in-depth context :

private AbstractDistanceScoreFunction parseVariable(String fieldName; XContentParser parser; QueryShardContext context;
  MultiValueMode mode) throws IOException {
  //the field must exist; else we cannot read the value for the doc later
  MappedFieldType fieldType = context.fieldMapper(fieldName);
  if (fieldType == null) {
  throw new ParsingException(parser.getTokenLocation(); "unknown field [{}]"; fieldName);
  // dates and time and geo need special handling
  if (fieldType instanceof DateFieldMapper.DateFieldType) {


Run the Check-Up to get a customized report like this:

Analyze your cluster