I'm doing some cleanup on my cluster and saw that there are a couple of small system indices that I'm not sure for what they are used.
Those indices are mostly
As the name made it clear, they are associated to the Index Lifecycle Management and Snapshot Lifecycle Management, but I'm not sure what is the use or if I can remove them.
One of most repeated recomendations from Elastic is to avoid to have lot of small indices and yet the Elasticsearch itself keeps creating those small indices.
ilm-history-ilm-policy are using the default settings for rollover with 30 days or 50 GB, the
slm-history-ilm-policy has a delete phase after 90 days, but the
ilm-history-ilm-policy does not have a delete phase.
My question is, what are these indices used for? It is safe to change the delete phase for something like 1 or 2 days?