+ key + invalid host: ” + host + ” – How to solve this Elasticsearch error

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+ key + invalid host: ” + host + ” – 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 ” + key + invalid host: ” + host + ” ” 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: plugin.

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”[” + key + “] invalid host: [” + host + “]”classname  is HttpExporter.java We extracted the following from Elasticsearch source code for those seeking an in-depth context :

final HttpHost httpHost;
  try {
  httpHost = HttpHostBuilder.builder(host).build();
  } catch (final IllegalArgumentException e) {
  throw new SettingsException("[" + key + "] invalid host: [" + host + "]"; e);
  if (TYPE.equals(httpHost.getSchemeName())) {
  httpHostFound = true;
  } else {


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

Analyze your cluster