Managing Dangling Indices

Hi

I'm new to ES and have inherited a 3-node data/master cluster which continually logs the same set of DanglingIndices. All of the indices listed are closed. Some appear to be common to all 3 nodes, others only 2 or are unique to one node (the punctuation chars are me flagging which are common). Q: will re-opening these indices help clear these warnings?

[2020-02-13T00:00:00,717][WARN ][o.e.g.DanglingIndicesState] [es01] [[active_directory-2019.06.03/mT7xf14iRHuTBj-d5CbYqw]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
.[2020-02-13T00:00:00,717][WARN ][o.e.g.DanglingIndicesState] [es01] [[active_directory-2019.06.04/F8_uB9rZRzuAvc1GzI6Thw]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
>[2020-02-13T00:00:00,717][WARN ][o.e.g.DanglingIndicesState] [es01] [[active_directory-2019.07.22/53CMdUIXTduIluYNIfSUwA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,717][WARN ][o.e.g.DanglingIndicesState] [es01] [[active_directory-2019.07.23/xkewdjcaTVWijRsgy3yYsg]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
,[2020-02-13T00:00:00,717][WARN ][o.e.g.DanglingIndicesState] [es01] [[active_directory-2019.07.24/UremXNg9QZaEfBz6MSJUzg]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,717][WARN ][o.e.g.DanglingIndicesState] [es01] [[active_directory-2019.07.25/KbR9H_OwQtyYHE6ODaytRA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata

.[2020-02-13T00:00:00,540][WARN ][o.e.g.DanglingIndicesState] [es02] [[active_directory-2019.06.04/F8_uB9rZRzuAvc1GzI6Thw]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,535][WARN ][o.e.g.DanglingIndicesState] [es02] [[active_directory-2019.06.09/JaAZ0TXTQx2L-9lEWHTgDQ]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
>[2020-02-13T00:00:00,540][WARN ][o.e.g.DanglingIndicesState] [es02] [[active_directory-2019.07.22/53CMdUIXTduIluYNIfSUwA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
,[2020-02-13T00:00:00,540][WARN ][o.e.g.DanglingIndicesState] [es02] [[active_directory-2019.07.24/UremXNg9QZaEfBz6MSJUzg]] can not be imported as a dangling index, as index with same name already exists in cluster metadata

>[2020-02-13T00:00:00,557][WARN ][o.e.g.DanglingIndicesState] [es03] [[active_directory-2019.07.22/53CMdUIXTduIluYNIfSUwA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,557][WARN ][o.e.g.DanglingIndicesState] [es03] [[active_directory-2019.07.22/SafMqX78QJCIbdyw6OdmeA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,557][WARN ][o.e.g.DanglingIndicesState] [es03] [[active_directory-2019.07.23/MaAVpRp-RXyxzHM2q3HUyQ]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,557][WARN ][o.e.g.DanglingIndicesState] [es03] [[active_directory-2019.07.24/nDjy2RSARIq5hyO6NfMvtA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
,[2020-02-13T00:00:00,557][WARN ][o.e.g.DanglingIndicesState] [es03] [[active_directory-2019.07.24/UremXNg9QZaEfBz6MSJUzg]] can not be imported as a dangling index, as index with same name already exists in cluster metadata
[2020-02-13T00:00:00,554][WARN ][o.e.g.DanglingIndicesState] [es03] [[active_directory-2019.07.25/J94IJoTPTquIt7mw44usXA]] can not be imported as a dangling index, as index with same name already exists in cluster metadata

thank you

This indicates that something might have gone quite wrong with your cluster on the dates mentioned, and you might have lost data then.

The preferred way to clean these indices up is to delete the existing indices, e.g. active_directory-2019.06.03 to allow these dangling indices to be imported in their place. You can then delete the dangling index if you don't want it, and then restore the original index from a snapshot; alternatively you can restore the original index with a different name which will give you access to both the original and dangling copies.

Thanks for the speedy response, David. I'll put your advice into action asap