Ah I did something similar at the university I worked at as a student. Everything was already set to network boot as the first step, so I set up a PXE server that loaded up DBAN. When we needed to wipe a lab before decommissioning, we'd flip their network to the PXE DBAN network, tell them all to reboot, and decom them in the morning.

Saved us a bunch of hours we then used to play Minecraft haha

I'm guessing you use WipeOS to more easily handle securely erasing disks. Could you have iVentoy host WipeOS to simplify the setup?

I've set up PXE booting at two previous companies for very different use cases.

The first was to automate server deployment; we ran bare metal servers, and even though we had managed hosting in our data centre the installation, configuration, and deployment of a server could potentially take days since it was just me doing it and I had other things to do.

So one day I set to work. I installed an Ubuntu server the same way I always did and then captured the debconf configuration to turn into a preseed file. I set up the disk partitioning, etc., and configured the OS to boot from DHCP. Then I configured the DHCP server with MAC addresses for every server we got and an associated IP address so that a given physical server would always get the same IP address.

Then I set up an internal apt repository; that's where I put custom packages, backports I had to recompile, third-party packages (e.g. perconadb) and so on.

Lastly, I set up salt (the management orchestration tool, like puppet or chef or ansible) with a nice simple (detailed) configuration.

The machines would be configured to boot via PXE. They'd load the kernel and initrd, which contained the preseed file that answered all of the installation/configuration questions. Lastly it ran the post-install shell script which started salt and ran the initial configuration, much of which was based on hostname. This would turn the current DHCP-provided IP address into a static networking configuration so that the server wasn't reliant on DHCP anymore; it would ensure that SSH keys were installed, and that the right services were enabled or disabled, install some packages based on the hostname (which represented the role, e.g. db02.blah.blah got percona installed). I also had some custom data sources (whatever you would call them) so that I could install the right RAID controller software based on which PCI devices were present; after all that, it would reboot. Once it rebooted from the local disk, salt would pick back up again and do the rest of the configuration (now that it wasn't running from a chroot and had all the required systemd services running). What used to take me several days to do for two servers turned into something one of our co-ops could do in an hour.

Second was another company that wanted to standardize the version of Linux its developers were running. Again, I set up an Ubuntu installer and configured it to boot iPXE and then fetch the kernel and the root image via HTTPS. The Ubuntu installer at that point was a Snap, and the default 'source' was a squashfs file that it unpacked to the new root filesystem before proceeding with package installation. I set up some scripts and configurations to take the default squashfs filesystem, unpack it, install new packages via apt in a chroot, and then repack it again. This let me do things like ensure Firefox, Thunderbird, and Chrome were installed and configured not from snaps; update to the latest packages; make sure Gnome was installed, etc. A lot of that was stuff the installer would do, of course, but given we were on gigabit ethernet it was significantly faster to download a 2 GB squashfs file than to download a 512M squashfs file and then download new or updated packages. One again what used to start with "Here's a USB, I think it has the latest Ubuntu on it" and take most of a day turned into "Do a one-off boot from the network via UEFI, choose a hostname, username, and password, and then just wait for twenty minutes while you get a coffee or meet your coworkers". I even found a "bug" (misbehaviour) in the installer where it would mount the squashfs and then rsync the files, which seemed significantly slower because the kernel was only using one thread for decompressing; using `unsquashfs` could use all cores and was dramatically faster, so I got to patch that (which I'm not sure ever made it into the installer anyway).

The one thing I couldn't make work was the OEM installation, where you put everything down onto the system unattended then put the user through the Ubuntu OOBE process. That would have made it far easier to pre-provision systems for users ahead of time; I did replace the default Plymouth splash screen logo with our company logo though, which was pretty cool.

I also set up network booting of macOS at another job, but that's sort of a very different process because it has all its own tooling, etc. for managing and Apple ended up moving from custom deployment images to static images and MDM for post-install configuration.

TL;DR network booting is pretty great actually; it's a very niche use case but if you're clever you can get a lot done. There's also lots of options for booting into a bootloader that can then present other options, allowing you to choose to netboot Ubuntu Desktop, Ubuntu Server, Windows, RHEL, Gentoo, a rescue image, or anything else you want.

Agreed, PXE seems ideal for provisioning things, but it's just too hard to use, especially when you're not on a network you fully control.

I just want to start the computer, and have it download an immutable OS image from somewhere I decide (and supply a checksum for, etc). I don't want to set up TFTP or any of this other stuff. It feels like I should be able to just specify an IP (let's say) a checksum (maybe supply that information to the NIC directly somehow), and be off to the races after a reboot.

I've not found this at all -- PXE "just works" on legacy boot or UEFI for me. I've used it for years to install hosts via Foreman (https://theforeman.org/), as well as for personal stuff on my home network, and it's so much better than getting people to use USB sticks or whatever else!

I’m confused, are you talking about getting PXE enabled in the hardware, or customizing something about your PXE software for the new hardware?

we need to go /stalinmode/ on the whole bootup and initialization industry subsector. it should be required by law for that stuff to be open source and documented.

"but muh competitive advantage??"

its literally a for loop that reads sectors from disk/network into memory and jumps to the start address.

if a local build of the (vendor provided source code) firmware doesn't match the checksum of the build thats flashed on the actual mobo, you get sent to a cobalt mine.

Yeah in order to automate, you’ve gotta know something about what you’re automating. PXE is not different.

You don't need to turn off STP, usually it's enough to set the forward delay to a very small value ("port fast" in cisco commands). If there is a loop, the port will usually still detect it, you at the most get a handful of multiplied packets.

And all the "http boot" firmware I've seen either always ignores certificate errors or doesn't do TLS anyways.

> There's also a new "https boot", which is supposed to be a PXE replacement, but TLS certs have time validity windows, and some clients may not have an RTC, or might have a dead CMOS battery, and those might not boot if the date is wrong.

I think the lack of entropy right after boot can also be a problem for the RNG. But, maybe that has been solved in more modern hardware.

You can also do things like boot with PXE (Legacy or UEFI PXE boot) to get a small image like iPXE, and then have iPXE do the http boot part. This means that you have an extra shim but you can pull larger images than TFTP is any good for.

TFTP is also UDP and I don't think it is pipelined, so it's all req->ack->req->ack, so any additional latency hits it hard too.

They let you boot off HTTPS? That explains why corp IT pushed out a Dell BIOS vulnerability update today relating to OpenSSL in my BIOS.