Thanks, I will check the TRACE log.
Meanwhile it rolled over - but probably for other reasons that I’d expected:
Desired balance computation for [37] is still not converged after [3.2h] and [1] iterations
Cluster health status changed from [YELLOW] to [GREEN] (reason: [shards started [[.ds-logs-prod2-nlc-2025. 09.23-000002][0]]]).
Data stream lifecycle successfully rolled over datastream [logs-prod2-nlc] due to the following met rollover conditions [[max_age: 1 d], [min_docs: 1]]. The new index is [.ds-logs-prod2-nlc-2025.09.23-000002]
[.ds-logs-prod2-nlc-2025.09.23-000002/gjKaOODPRvGWUCdaH8qjVQ] update_mapping [_doc]
[.ds-logs-prod2-nlc-2025.09.23-000002/gjKaOODPRvGWUCdaH8qjVQ] update_mapping [_doc]
[.ds-logs-prod2-nlc-2025.09.23-000002/gjKaOODPRvGWUCdaH8qjVQ] update_mapping [_doc]
Data stream lifecycle service successfully updated settings [[index.merge.policy.merge_factor, index.merge.policy.floor_segment]] for index index [.ds-logs-prod2-nlc-2025.09.22-000001]
Data stream lifecycle is issuing a request to force merge index [.ds-logs-prod2-nlc-2025.09.22-000001]
Data stream lifecycle successfully force merged index [.ds-logs-prod2-nlc-2025.09.22-000001]
[.ds-logs-prod2-nlc-2025.09.23-000002/gjKaOODPRvGWUCdaH8qjVQ] update_mapping [_doc]
It looks like the rollover happened after 1d.
Also is it normal to see a force merge? The docs say that it should rather do a “tail merge” (whatever that exactly means)…
Could it be that I still see some remains of the previously configured ILM policy on the index (even though prefer_ilm is false now)?