Automation

Clicking through the Proxmox web UI to build a VM is fine the first few times. It stops being fine once you’re rebuilding the same handful of VMs for the fifth time after a test, or trying to remember exactly which CPU type, disk size, and network bridge you used for a box six months ago. Terraform (or its open-source fork OpenTofu, which this article treats as interchangeable since the Proxmox providers work with either) fixes that by making the VM’s configuration a text file instead of a memory. This is not about replacing Proxmox’s own tooling, it’s about not having to rebuild a guest from memory ever again. ...

Every homelab operator hits the same wall eventually: you need a fifth Ubuntu VM for some new service, and the thought of walking through another OS installer, setting the hostname, adding your SSH key, and running updates makes you want to just leave the last one running forever instead. Cloud-init templates fix this. Build the template once, and every new VM after that is a clone plus a few lines of config, done in under a minute instead of fifteen. This is the same workflow cloud providers use to spin up instances on demand, and Proxmox supports it natively, no extra tooling required to get the basics working. ...