Host list for key is empty but type is type – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 7.5-8.9

Briefly, this error occurs when Elasticsearch is unable to find any hosts for a specific key and type. This could be due to incorrect configuration settings or network issues. To resolve this, you can check your Elasticsearch configuration to ensure that the host list for the specified key and type is correctly defined. Also, verify your network connectivity to ensure that the hosts are reachable. If the issue persists, you may need to check your Elasticsearch logs for more detailed error information.

This guide will help you check for common problems that cause the log ” host list for [” + key + “] is empty but type is [” + type + “] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.

Log Context

Log “host list for [” + key + “] is empty but type is [” + type + “]” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 final String defaultType = Exporter.TYPE_SETTING.getConcreteSettingForNamespace(namespace).get(Settings.EMPTY);
 if (Objects.equals(type; defaultType)) {
 // hosts can only be empty if the type is unset
 } else {
 throw new SettingsException("host list for [" + key + "] is empty but type is [" + type + "]");
 }  boolean httpHostFound = false;
 boolean httpsHostFound = false;