@george1421 Done.

With the assistance of @george1421 in this thread, I arrived at the following process.

Features

• Unattended installation, preseeded (using a preseed.cfg)
• Completely hands-off, after selecting the appropriate FOG menu item on PXE boot
• Based on Debian’s netboot - no need to download the Debian ISO
• Uses HTTP only (though you could swap in NFS, TFTP, etc., if you prefer)
• The three files required for the installation can reside in a single location on the FOG server
• Process can be generalised to other versions of Debian and other OSes (though you’d need to work out the Kickstart part for RedHat distros, etc.)
• Works with UEFI - I repeat, works with UEFI!!!

Process

On the FOG server, Unpack netboot.tar.gz to a folder under the Apache root, e.g.:

mkdir -p /home/fogproject/www/os/debian/10.7N
cd /home/fogproject/www/os/debian/10.7N
wget http://ftp.nl.debian.org/debian/dists/buster/main/installer-amd64/current/images/netboot/netboot.tar.gz
tar zxf netboot.tar.gz
rm netboot.tar.gz
chown -R apache:apache /home/fogproject/www/os/debian/10.7N

Note that I relocated my www root to /home/fogproject. Yours may still be at /var/www. or similar.

The above unpacks:

debian-installer/
pxelinux.0@
pxelinux.cfg@
version.info

We only really need two files, which are in the debian-installer directory: linux and initrd.gz. Still, I leave this folder structure as it is.

Place your preseed file (normally preseed.cfg) in the same directory as the netboot files above (/home/fogproject/www/os/debian/10.7N in my example). The content of your preseed file is entirely up to you. See the official example, to get started.

Create a FOG menu entry as follows:

Menu item: os.Debian.10.7.auto.UEFI
Description: Unattended Debian 10.7 installation (UEFI)
Parameters:

kernel http://${fog-ip}/os/debian/10.7N/debian-installer/amd64/linux auto=true url=http://${fog-ip}/os/debian/10.7N/preseed.cfg interface=auto hostname=debian-10 domain=local initrd=initrd.gz vga=788 noprompt quiet
imgfetch http://${fog-ip}/os/debian/10.7N/debian-installer/amd64/initrd.gz
boot || goto MENU

Menu Show with: All hosts

Notes

If you need an option for manual installation, simply drop the auto parameters from the kernel line:

kernel http://${fog-ip}/os/debian/10.7N/debian-installer/amd64/linux initrd=initrd.gz vga=788 quiet

The clue to getting this working was to include initrd=initrd.gz in the kernel line and then use imgfetch to make initrd.gz available.

@george1421 George, firstly thanks again for the all the work you’ve put into this!

This steered me in exactly the right direction. The following are the parameters I used for a completely automated netboot install (no Live ISO required). This is the point I was hoping to get to. Brilliant.

kernel tftp://${fog-ip}/debian-installer/amd64/linux auto=true url=http://${fog-ip}/os/autoinstall/debian-10/preseed.cfg interface=auto hostname=debian-10 domain=local initrd=initrd.gz vga=788 noprompt quiet
imgfetch tftp://${fog-ip}/debian-installer/amd64/initrd.gz
boot || goto MENU

So this removes the need to mess around with grub.cfg or boot to an intermediate (grub) menu. All you need are the netboot.tar.gz files and a preseed.cfg. Next I’ll try doing this all via HTTP (rather than TFTP), to avoid polluting /tftpboot. I’m mindful that I would like to make the backup and restoration of FOG itself as straightforward as possible.

I know I’ve said this a few times in this thread (!) but once more: thank you. If I can help by writing up a wiki page for this process, do point me in the right direction.

Yep, HTTP worked perfectly too, which means I could put the three required files in a single location under the web root. FOG menu parameters:

kernel http://${fog-ip}/os/autoinstall/debian-10/debian-installer/amd64/linux auto=true url=http://${fog-ip}/os/autoinstall/debian-10/preseed.cfg interface=auto hostname=debian-10 domain=local initrd=initrd.gz vga=788 noprompt quiet
imgfetch http://${fog-ip}/os/autoinstall/debian-10/debian-installer/amd64/initrd.gz
boot || goto MENU

This is clean & efficient. I like it. Probably not as quick as using a Live image, but I’m doing this over a fast internet connection and it’s a minimal install. So the whole thing is done in ten minutes or so.

Again, I’m more than willing to write this up somewhere if useful for others.