Ok everyone, I'm home from site.
I'm relatively confident the issue is with the installation scripts (probably hard-coding mounting a CD/DVD). I don't think the hardware being different is going to make the boot methodology change. The box itself isn't a HCL qualified dell server, but I seriously doubt it'l make any difference to the installation scripts attempting to mount a CD/DVD.
The VMware installations are likely working fine because the ISO installation method in VMWare mounts via an emulated CD/DVD player.
Can someone else just do a quick check of a baremetal install using latest ISOmorphic and latest R80.20 managemet ISO to see if they can replicate? (perhaps QA was only done using virtualbox / vmware and not baremetal for R80.20).
I will probably end up running this on a the free ESXi hypervisor in the end.
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I'll try and make this as clear as I can.
Booting from the R80.20 Management (T101) ISO image (created with the latest ISOmorphic) via a known good USB stick.
I get a good bootloader, select options for either with ACPI + VGA or without ACPI + VGA (I believe it's 11 or 12).
Loader successfully boots the kernel and executes the Installer with the ncurses front end. Immediately afterwards I see attempts to mount the CD-ROM which fail, then the main console reports failed installation.
Here are the screenshots:
Normal post from tty1 (ALT-F2). DIsk found, usb-storage loaded..
From tty2 (ALT-F3) - for some reason trying to mount a CD device (?).
This is a new boot with the DVD device disabled in the bios. CD device sda?
Here is the final error on main console (tty1 / ALT-F1).