• Editing grub/EFI config on an installer ISO for serial install

    From Andy Smith@21:1/5 to All on Sun Jul 28 12:30:01 2024
    Hi,

    I am used to installing Debian by PXE and serial console. For that
    purpose I'm familiar with editing the isolinux config files to have
    the kernel serial settings (console=ttyS… etc) in isolinux/txt.cfg.

    Now for the first time I am trying to install a system that has a
    management controller that adds virtual media from ISOs, but I would
    still like to see that install over the IPMI serial.

    Currently when I add the Debian 12 netinst ISO as a virtual media it
    EFI boots grub, not isolinux, so the output of grub only goes to the
    graphical terminal (a web interface of the BMC in this case).

    I can then force the install to proceed over serial by editing the
    "Install" option and adding the familiar:

    --- console=ttyS1,115200n8

    pn the end of the kernel line, and that works, so I am nearly there.

    I'd really like for this thing to boot grub in text mode on the
    serial console though.

    I guess I need to find the grub configuration that is in use from
    the ISO and add the usual

    serial --unit=1 --speed=115200 --word=8 --parity=no --stop=1
    terminal_input serial
    terminal_output serial

    Should I just edit that into $iso_root/boot/grub/grub.cfg and repack
    the ISO?

    Is there any documentation page about this? Everything I found so
    far just covers the isolinux bit, which doesn't appear to be
    relevant here.

    Thanks,
    Andy

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)