Ignoring dangled index on node – How to solve this Elasticsearch error

Opster Team

Aug-23, Version: 6.8-7.15

Briefly, this error occurs when Elasticsearch detects an index that is not recognized in the cluster state. This is known as a “dangled” index. It can happen due to various reasons like abrupt shutdown or data corruption. To resolve this issue, you can manually import the dangled index using the import dangling index API. Alternatively, you can set the ‘gateway.auto_import_dangling_indices’ to true to automatically import them. However, be cautious as this could lead to data inconsistency across nodes. Always ensure to have a backup of your data to prevent loss.

This guide will help you check for common problems that cause the log ” ignoring dangled index [{}] on node [{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: index, node, dangled.

Log Context

Log “ignoring dangled index [{}] on node [{}]” classname is LocalAllocateDangledIndices.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

                        if (currentState.nodes().getMinNodeVersion().before(indexMetadata.getCreationVersion())) {
                            logger.warn("ignoring dangled index [{}] on node [{}]" +
                                " since its created version [{}] is later than the oldest versioned node in the cluster [{}]";
                                indexMetadata.getIndex(); request.fromNode; indexMetadata.getCreationVersion();