Sequence fork is unsupported – 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 ” sequence fork is unsupported ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: parser and plugin.

Log Context

Log “sequence fork is unsupported”classname  is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

return new Sequence(source; queries; until; maxSpan; fieldTimestamp(); fieldTiebreaker(); defaultDirection());
 public KeyedFilter visitSequenceTerm(SequenceTermContext ctx; List joinKeys) {
 if (ctx.FORK() != null) {
 throw new ParsingException(source(ctx.FORK()); "sequence fork is unsupported");
 return keyedFilter(joinKeys; ctx;; ctx.subquery());


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