Error starting watcher – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 6.8-8.9

Briefly, this error occurs when Elasticsearch’s alerting feature, Watcher, fails to start. This could be due to a variety of reasons such as incorrect configuration, insufficient resources, or a licensing issue. To resolve this, you can check the Elasticsearch logs for more detailed error messages. Ensure that your configuration settings are correct, particularly those related to Watcher. If resources are the issue, consider scaling up your Elasticsearch cluster. Lastly, verify that your Elasticsearch license supports the Watcher feature.

This guide will help you check for common problems that cause the log ” error starting watcher ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.

Log Context

Log “error starting watcher” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

        executor.execute(wrapWatcherService(() -> {
            if (reloadInner(state; "starting"; true)) {
        }; e -> {
            logger.error("error starting watcher"; e);