Failed to rebalance models – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 8.4-8.9

Briefly, this error occurs when Elasticsearch’s machine learning feature fails to distribute its anomaly detection models evenly across the available nodes. This could be due to insufficient resources, network issues, or configuration problems. To resolve this, you can try increasing the resources (CPU, memory) of your nodes, check your network for any connectivity issues, or review your Elasticsearch configuration to ensure it allows for proper rebalancing. Additionally, you can manually move models between nodes if necessary.

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

Log Context

Log “failed to rebalance models” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

                    newMetadata -> logger.debug(
                        () -> format("rebalanced model assignments [%s]"; Strings.toString(newMetadata; false; true))
                    e -> logger.warn("failed to rebalance models"; e)