I like my Linux installs heavily customized and security hardened, to the extent that copying over /home won't cut it, but not so much that it breaks when updating Debian. Whenever someone mentions reinstalling Linux, I am instinctively nervous thinking about the work it would take for me to get from a vanilla install to my current configuration.

It started a couple of years ago, when dreading the work of configuring Debian to my taste on a new laptop, I decided to instead just shrink my existing install to match the new laptop's drive and dd it over. I later made a VM from my install, stripped out personal files and obvious junk, and condensed it to a 30 GB raw disk image, which I then deployed on the rest of my machines.

That was still a bit too janky, so once my configuration and installed packages stabilized, I bit the bullet, spun up a new VM, and painstakingly replicated my configuration from a fresh copy of Debian. I finished with a 24 GB raw disk image, which I can now deploy as a "fresh" yet pre-configured install, whether to prepare new machines, make new VMs, fix broken installs, or just because I want to.

All that needs to be done after dd'ing the image to a new disk is:

  • Some machines: boot grubx64.efi/shimx64.efi from Ventoy and "bless" the new install with grub-install and update-grub
  • Reencrypt LUKS root partition with new password
  • Configure user and GRUB passwords
  • Set hostname
  • Install updates and drivers as needed
  • Configure for high DPI if needed

I'm interested to hear if any of you have a similar workflow or any feedback on mine.

  • Unmapped@lemmy.ml
    ·
    4 months ago

    You should check out Nixos. You make a config file that you can just copy over to as many machines as you want.

    • wheresmysurplusvalue [comrade/them]
      ·
      4 months ago

      Yeah this is a good use case for it, if I remember right you can also trivially generate a live installer iso from the same nix configuration you'd use to run any usual updates. So you can make a custom installer for your exact configuration and copy that onto a flash drive to bootstrap you into a working environment. I think the live installer would generate something like a hardware-configuration.nix too.

      • thejevans@lemmy.ml
        ·
        4 months ago

        You could also use nixos-anywhere + disko. This is what I use. If you have SSH and root access to a linux machine, you can live swap to a NixOS installer, load a configuration over SSH, install and reboot. It gives a similar experience to Ansible.

        • wheresmysurplusvalue [comrade/them]
          ·
          4 months ago

          That's sweet, I didn't think about using nixos-anywhere for this purpose (just simplifying the install process on a new machine). I used it to great success to install NixOS on a VPS that only had a few OS options like Debian.

    • 4am@lemm.ee
      ·
      4 months ago

      That or Ansible, if you will have a machine to deploy from

  • oscardejarjayes [comrade/them]
    ·
    4 months ago

    You could try using Hashicorp's Packer to generate images repeatably (usually more meant for cloud images though). Or NixOS (like others have mention), or Guix (like NixOS, but better in some ways, worse in others). You could make it an Ansible playbook, which would let you both make configured images, and just configure machines that already have an OS.

    I do something similar with archiso, fwiw, but that only works with Arch Linux.

    Would you want to change your distribution, or just keep Debian with some tools to automate?

    • Lichtblitz@discuss.tchncs.de
      ·
      4 months ago

      Ansible playbook is perfect for this. All your configuration is repeatable, whether on a running system or a new one. Plus you can start with a completely fresh newest version image and apply from there, instead of starting from a soon-to-be outdated custom image.

  • darius@lemmy.ml
    ·
    4 months ago

    I have the exact same workflow except I have two images: one for legacy/MBR and another for EFI/GPT -- once I read your post I was glad to see I'm not alone haha!

  • ezekielmudd@reddthat.com
    ·
    4 months ago

    I believe that Proxmox does this because I have installed/created containers from their available images. I wonder how they create those container images?

  • data1701d (He/Him)@startrek.website
    ·
    4 months ago

    You might be able to script something with Debootstrap. I tested Bcachefs on a spare device once and couldn't get through the standard Debian install process, so I ended up using a live image to Debootstrap the drive. You should be able to give a list of packages to install and copy over configs to the partition.