I pulled a 1 TB NVMe out of an old Windows box, dropped it in a USB enclosure and plugged it in. Windows showed nothing. No drive letter, no “initialize this disk” prompt, nothing in Explorer. Disk Management listed it as Invalid. The enclosure’s booklet said to “bring the disk online”, which silently did nothing. The data was completely intact. Windows was refusing on policy grounds, not because anything was broken. Getting it back meant going around the Windows…

Proxmox’s built-in cloud-init support is fine for the basics: a user, an SSH key, an IP config. It falls apart the second you want your own user-data, vendor-data or a real network-config. The GUI and the ci* options only expose a handful of fields. The escape hatch is cicustom pointing at snippet files, and that means getting files onto the Proxmox host’s filesystem first. The usual alternative is building a nocloud ISO yourself with genisoimage or mkisofs. That means a system…

If you start automating Proxmox VE through the API, one thing trips you up first. Almost nothing you ask it to do is finished when the HTTP call returns. Start a VM, clone a template, download an ISO to storage, delete a disk… the response is a single string that looks like a typo. The actual work is happening in a worker process on the node. If your next call depends on that work being done, you have to go find out when it’s done.