Are there any benefits of running Proxmox and virtualizing everything, vs having a host OS and running Docker and libvirt to host VMs for services that need it? I know that Proxmox does some storage management etc, but it seems like I could get everything it does with a well-managed host OS + ZFS/btrfs and using virtualization tools
I use both Proxmox and libvirt on Debian. I don’t use clustering. For me, the biggest advantages of PVE are:
On the other hand, there are a couple things I like more about libvirt:
I use libvirt for my most critical VMs (network infra like router, DNS, and DHCP). I strongly prefer PVE for anything where I’m going to be interacting with VMs regularly, like testing or lab setups.
This… It is ease vs control. If you have needs inside the box Proxmox has planned for, it is very easy. But if you want to step outside that box, you are in for a world of surprise. I install Proxmox for clients that do not have solid Linux chops. I run KVM/libvirt on my own stuff. And if you need a web front end, oVirt exists…