Unknown serialized type ” + ord + ” – How to solve this Elasticsearch error

Opster Team

March-22, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” unknown serialized type ” + ord + ” ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: query, index.

Log Context

Log “unknown serialized type [” + ord + “]”classname  is ZeroTermsQueryOption.java We extracted the following from Elasticsearch source code for those seeking an in-depth context :

for (ZeroTermsQueryOption zeroTermsQuery : ZeroTermsQueryOption.values()) {
 if (zeroTermsQuery.ordinal == ord) {
 return zeroTermsQuery;
 throw new ElasticsearchException("unknown serialized type [" + ord + "]");
 public void writeTo(StreamOutput out) throws IOException {


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