Only 4. You need a CD-ROM to complete the installation (https://www.serverbrain.org/troubleshooting-2000/install-by-using-setup-diskettes-and-a-cdrom.html)
If you have a machine with no current operating system on it that will not boot from a CD-ROM, you must use this method. Setup disks are a set of four disks that form a minimal installation of Windows 2000
I wasn’t aware there were CD-ROMs that you couldn’t boot from.
Hmm but you could always boot from DVD right? Thinking back to live operating systems run from disc.
I may be wrong but I think it’d be the same issue in that the bios wouldn’t boot the OS from that sort of drive. For whatever reason that caused it I think it’d be a similar issue. That said by the time DVD drives being common enough for a server drive, most BIOSs would be able to handle it fine and a fair bit of time after this was needed.
Though I kinda thought with proper configuration cd rom drives were all bootable, but I wasn’t working with servers in that era either so there were probably some mobos/bios that didn’t work properly for booting a cd/DVD drive. Closest to the time I was familiar with was XP and pretty sure that was expected to be CD bootable in 2001. So maybe this kicked in the bios support for bootable non floppy disc drives?
