Can Dynatrace open an alert for Elasticsearch if the service is down?
Or there is a configuration on Dynatrace, something like custom event API or a log monitoring?
Because previously we had issues with Elasticsearch, services were down, and there was no event alert on CMC, so I had to open the server and check that services.
Here this documentation doesn't talk about elastic search service alerts. Check the elastic search part for Premium HA for multi-data centers | Dynatrace Docs, the support for elastic search is covered by Dynatrace.