Log Failed to merge – How To Solve Related Issues

Log Failed to merge – How To Solve Related Issues

Updated: Feb-20

Elasticsearch Version: 1.7-8.0


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To troubleshoot log “Failed to merge” it’s important to understand a few problems related to Elasticsearch concepts index, merge. See bellow important tips and explanations on these concepts

Log Context

Log”failed to merge” classname is InternalEngine.java
We extracted the following from Elasticsearch source code for those seeking an in-depth context :


        protected void handleMergeException(final Directory dir; final Throwable exc) {
            logger.error("failed to merge"; exc);
            if (config().getMergeSchedulerConfig().isNotifyOnMergeFailure()) {
                engineConfig.getThreadPool().generic().execute(new AbstractRunnable() {
                    public void onFailure(Throwable t) {
                        logger.debug("merge failure action rejected"; t);

Related issues to this log

We have gathered selected Q&A from the community and issues from Github, that can help fix related issues please review the following for further information :


Index Failed To Merge  


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