[dith3r]

I'm hosting own MySQL, Mongo and Elastic clusters. At the beginning it takes more time to setup than cloud providers solutions and require more knowledge and tooling to do some ops(upgrades, backups etc). But you know which version of db you are running and how it is configured. Additionally cloud providers own solutions are binding with one of them.

[vira28]

Agree. It's a trade-off. If one knows how to do a bit of ops then it's feasible to self-host.

what's the scale of the application(s) that uses these data stores? How do you monitor these clusters?

[dith3r]

Std. Grafana + Prometheus + node exporter + specific data source exporter