Fatal exception while booting Elasticsearch – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 8.3-8.9

Briefly, this error occurs when Elasticsearch encounters a critical issue during its startup process. This could be due to a variety of reasons such as incorrect configuration settings, insufficient system resources, or corrupted data files. To resolve this issue, you can check the Elasticsearch logs for more detailed error messages. You may need to adjust your configuration settings, allocate more system resources, or restore your data from a backup. If the problem persists, you may need to reinstall Elasticsearch.

This guide will help you check for common problems that cause the log ” fatal exception while booting Elasticsearch ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: bootstrap.

Log Context

Log “fatal exception while booting Elasticsearch” classname is Bootstrap.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :


    void exitWithUnknownException(Throwable e) {
        Logger logger = LogManager.getLogger(Elasticsearch.class);
        logger.error("fatal exception while booting Elasticsearch"; e);
        gracefullyExit(1); // mimic JDK exit code on exception

    private void gracefullyExit(int exitCode) {