Corrupt file detected source merge but is set to – How to solve related issues

Opster Team

Feb-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” Corrupt file detected source merge but is set to ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: discovery-file and index.

Log Context

Log “corrupt file detected source: [merge] but [{}] is set to [{}]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

         public void onFailedMerge(MergePolicy.MergeException e) {
            if (Lucene.isCorruptionException(e)) {
                if (engineConfig.isFailEngineOnCorruption()) {
                    failEngine("corrupt file detected source: [merge]"; e);
                } else {
                    logger.warn("corrupt file detected source: [merge] but [{}] is set to [{}]"; e; EngineConfig.INDEX_FAIL_ON_CORRUPTION_SETTING; engineConfig.isFailEngineOnCorruption());
            } else if (engineConfig.isFailOnMergeFailure()) {
                failEngine("merge exception"; e);


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