Opster Team
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This guide will help you check for common problems that cause the log ” Metadata state not restored; reason: ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: metadata.
Overview
Metadata in Elasticsearch refers to additional information stored for each document. This is achieved using the specific metadata fields available in Elasticsearch. The default behavior of some of these metadata fields can be customized during mapping creation.
Examples
Using _meta meta-field for storing application-specific information with the mapping:
PUT /my_index?pretty { "mappings": { "_meta": { "domain": "security", "release_information": { "date": "18-01-2020", "version": "7.5" } } } }
Notes
- In version 2.x, Elasticsearch had a total 13 meta fields available, which are: _index, _uid, _type, _id, _source, _size, _all, _field_names, _timestamp, _ttl, _parent, _routing, _meta
- In version 5.x, _timestamp and _ttl meta fields were removed.
- In version 6.x, the _parent meta field was removed.
- In version 7.x, _uid and _all meta fields were removed.
Log Context
Log “Metadata state not restored; reason: {}” classname is GatewayService.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
Override public void onFailure(String message) { recovered.set(false); scheduledRecovery.set(false); // don't remove the block here; we don't want to allow anything in such a case logger.info("metadata state not restored; reason: {}"; message); } } // used for testing
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Jose Rafaelly
Head of System Engineering at Everymundo