Upgrading Proxmox: No-Subscription Repos, apt Pinning, and Surviving a Major Version Jump
Every fresh Proxmox install nags you about a missing subscription the first time you log into the web UI, and most homelab operators click past it, point apt at the no-subscription repo, and never think about the update process again until something breaks. That’s fine for routine point releases. It stops being fine the day you need to jump across a major version (7 to 8, 8 to 9, whatever the next one is), because that’s the one update that can genuinely strand VMs, break a cluster’s quorum, or leave a ZFS pool on a format the old kernel can’t mount if you do it carelessly. The repo choice and the upgrade sequence are two separate things worth understanding on their own. ...