Delete warmer – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 1.7-1.7

Briefly, this error occurs when you’re trying to delete a non-existent Elasticsearch warmer. Elasticsearch warmers are used to pre-run searches to improve search speed. However, they were deprecated in version 2.3.0 and completely removed in version 5.0.0. To resolve this issue, you should first check your Elasticsearch version. If it’s 5.0.0 or later, you don’t need to delete warmers as they don’t exist. If it’s earlier than 5.0.0, ensure the warmer you’re trying to delete actually exists. If it doesn’t, you’ll need to create it before you can delete it.

This guide will help you check for common problems that cause the log ” [{}] delete warmer [{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: admin, delete, indices and warmer.

Log Context

Log “[{}] delete warmer [{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

                         IndexWarmersMetaData warmers = indexMetaData.custom(IndexWarmersMetaData.TYPE);
                        if (warmers != null) {
                            for (IndexWarmersMetaData.Entry entry : warmers.entries()) {
                                for (String warmer : request.names()) {
                                    if (Regex.simpleMatch(warmer; || warmer.equals("_all")) {
                              "[{}] delete warmer [{}]"; index;;