Authentication to realm failed - - Common causes and quick fixes

Authentication to realm failed – – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 6.8-8.9

Briefly, this error occurs when Elasticsearch cannot authenticate a user due to incorrect credentials or misconfigured authentication settings in the Elasticsearch realm. To resolve this issue, you can: 1) Verify the user credentials are correct and try again. 2) Check the authentication settings in the Elasticsearch realm and ensure they are correctly configured. 3) If using an external authentication service, ensure it is properly connected and functioning. 4) Check the Elasticsearch logs for more detailed error information.

This guide will help you check for common problems that cause the log ” Authentication to realm {} failed – {}{} ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.

Log Context

Log “Authentication to realm {} failed – {}{}” classname is RealmsAuthenticator.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

        ActionListener> listener
    ) {
        messages.forEach((realm; tuple) -> {
            final String message = tuple.v1();
            final String cause = tuple.v2() == null ? "" : " (Caused by " + tuple.v2() + ")";
            logger.warn("Authentication to realm {} failed - {}{}"; realm.name(); message; cause);
        });
        if (context.getUnlicensedRealms().isEmpty() == false) {
            logger.warn(
                "Authentication failed using realms [{}]."
                    + " Realms [{}] were skipped because they are not permitted on the current license";