[Debian](https://debian.org) what to say about Debian, I have it on my Desktop and all of my Servers since around version 4.0. On my Desktop i use Debian Testing/sid.
Im a big fan of [Proxmox](https://proxmox.com/en/), I use theier [Virtual Environment](https://proxmox.com/en/proxmox-ve) which runs both LXC and KVM Machines since a long time and the [Backup Server](https://proxmox.com/en/proxmox-backup-server) since it's out there. It's just ROCK Stable.
[k3s](https://k3s.io/) the lightweight alternative to Kubernetes Mainline, you can select your K/V storage, so no etcd which is using all of my disk IO/s :)
I have all my Domains in a splitdns environment for that I use a [PowerDNS](https://www.powerdns.com/) and [phpIPAM](https://phpipam.net/) as Mangement UI.