The index.lifecycle.indexing_complete setting indicates to index lifecycle management whether this index has already been rolled over. If it is set to true, that indicates that this index has already been rolled over and does not need to be rolled over again. Therefore, index lifecycle management will skip any Rollover Action configured in the associated lifecycle policy for this index. This is useful if you need to make an exception to your normal Lifecycle Policy and switching the alias to a different index by hand, but do not want to remove the index from index lifecycle management completely.

This setting is set to true automatically by ILM upon the successful completion of a Rollover Action. However, it will be removed if the policy is removed from the index.

If index.lifecycle.indexing_complete is set to true on an index, it will not be rolled over by index lifecycle management, but index lifecycle management will verify that this index is no longer the write index for the alias specified by index.lifecycle.rollover_alias. If that setting is missing, or if the index is still the write index for that alias, this index will be moved to the error step.

For example, if you wish to change the name of new indices while retaining previous data in accordance with your configured policy, you can create the template for the new index name pattern and the first index with the new name manually, change the write index of the alias using the Index Aliases API, and set index.lifecycle.indexing_complete to true on the old index to indicate that it does not need to be rolled over. This way, index lifecycle management will continue to manage the old index in accordance with its existing policy, as well as the new one, with no interruption.