I've used this[1] Terraform provider together with the Talos[2] distribution for deploying a Kubernetes cluster. I agree that the APIs available with Proxmox are not fully featured, but it more than suits my needs.
I'm running a four node cluster on salvaged SFF machines backing up lvm snapshots to home brewed TruNAS storage and it all makes me happy.
I'm running a four node cluster on salvaged SFF machines backing up lvm snapshots to home brewed TruNAS storage and it all makes me happy.
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[1] https://github.com/Telmate/terraform-provider-proxmox
[2] https://factory.talos.dev/