Failed to clear cache for realms Arrays toString realmNames – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 8.3-8.9

Briefly, this error occurs when Elasticsearch fails to clear the cache for specific security realms. This could be due to a misconfiguration in the security settings or a lack of necessary permissions. To resolve this issue, you can try the following: 1) Check and correct the security settings in your Elasticsearch configuration file. 2) Ensure that Elasticsearch has the necessary permissions to clear the cache. 3) Restart the Elasticsearch service to refresh all settings and caches. 4) If the problem persists, consider upgrading Elasticsearch to the latest version as it might be a bug that has been fixed.

This guide will help you check for common problems that cause the log ” Failed to clear cache for realms [” + Arrays.toString(realmNames) + “] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin, cache.

Log Context

Log “Failed to clear cache for realms [” + Arrays.toString(realmNames) + “]” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

            new ClearRealmCacheRequest().realms(realmNames);
            ActionListener.wrap(response -> {
                logger.debug(() -> format("Cleared cached in realms [%s] due to role mapping change"; Arrays.toString(realmNames)));
            }; ex -> {
                logger.warn(() -> "Failed to clear cache for realms [" + Arrays.toString(realmNames) + "]"; ex);