Unknown day of week – How to solve this Elasticsearch error

Opster Team

July-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” unknown day of week ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.

Log Context

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

case "friday": return FRIDAY;
 case "7":
 case "sat":
 case "saturday": return SATURDAY;
 throw new ElasticsearchParseException("unknown day of week [{}]"; day);


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