Opster Team
Before you begin reading this guide, we recommend you run Elasticsearch Error Check-Up which analyzes 2 JSON files to detect many errors.
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This guide will help you check for common problems that cause the log ” Error executing ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: mustache.

Log Context
Log “Error executing” classname is MustacheScriptEngineService.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
public Object execute(CompiledScript template; Mapvars) { BytesStreamOutput result = new BytesStreamOutput(); try (UTF8StreamWriter writer = utf8StreamWriter().setOutput(result)) { ((Mustache) template.compiled()).execute(writer; vars); } catch (Exception e) { logger.error("Error executing " + template; e); throw new ScriptException("Error executing " + template; e); } return result.bytes(); }
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