Re: PXE booting a custom Debian installer hangs at "your installation media couldn't be mounted"

[Michael Paoli <michael.paoli@berkeley.edu>]

On Fri, Oct 31, 2025 at 3:42 AM Eike Sauer <eike.sauer@web.de> wrote:
> we're trying to install our system using a custom made installer ISO (based on the Debian installer) via PXE.
> Well, I wouldn't be here if it would work out. :)

So, have you first gotten PXE boot/install to work with
one of Debian's standard installation images?
I set that all up some years ago, worked perfectly fine.
And pretty sure I followed this wiki page for instructions/guide:
https://wiki.debian.org/PXEBootInstall

If you can get that to work perfectly fine without any issues,
then all you have left to do is the customization of your image,
at least presuming that's how you want to go about the customization.
There are, of course, also other possible means, e.g. preseed, etc.
and could pass such data via your PXE boot configuration, or
possibly other means.

I know at one point I had my PXE environment set up such
that the booted client would bring me to a menu, and from
there, I could then select which ISO image to boot.
But I haven't used that environment in some years,
so it would almost certainly need at least some updating
on its configuration, and some of its data, etc.

And, wiki page ... if something isn't fully correct there or needs updating,
well, it's a wiki.  :-)  So one could generally fix/improve that.