I may be the only one interested in this kind of thing, but the Fedora on ThinkPads news got me looking into Fedora again… after a long hiatus… This isn’t ThinkPad specific, although my current test machines are X1 Yogas and my typical targets are ThinkPads.
The back-story: I almost never need or want a bare-metal install of *nix these days (heresy!!!!) since I’m no longer maintaining Linux or Solaris drivers, but I do use live distros a lot. The advantage to using live distro media – even if on an internal HDD or SSD – is that it can be accessed and manipulated from Windows if in a FAT32 partition. There’s that heresy again… I “install” it on a secondary drive, or use it as the base for a “Swiss Army” flash drive or more recently an external NVMe SSD. Grub.conf can be edited (from Linux or Windows) to boot all sorts of things: other OS-en ISOs, forensic tools, backup software, etc… Typically my secondary drive or external pocket drive will have Linux live – multiple distros and versions, Acronis, Memtest, EFI Shell, and so on…
So, to Fedora… or actually Ubuntu first. Ubuntu has been my go-to base distro for donkey’s years until recently. They broke persistence – which is nearly a must-have for live media, and once they fixed that they broke the ability to loop-mount and boot an ISO – absolutely vital for what I do. That broke in 19.10 and remains a problem in 20.04 🙁
Now to Fedora… thought I’d give it a try and see if its version of grub will boot ISOs. The problem: my usual method of “installing” into a FAT32 partition doesn’t work 🙁 Normally I just pull the contents out of an ISO – Ubuntu, other Linux, Windows installer… – and toss it at a FAT32 flash drive or SSD (or even HDD) and we’re good to EFI boot. Fedora 32 done this way pulls up the grub menu but after selection my TP Yogas lock up. I can force the X1YG1 off but the X1YG4 refuses to honor a long press on the power button! Have to use the emergency reset hole. Yike!
The Fedora media creation tool builds a bootable drive but it generates an isofs (?) filesystem and shrinks the drive to 2GB. This isn’t easily accessible or editable, and doesn’t allow me to add other tools to ISO-boot or chainload. No place to put recovered data if that’s what the drive is being used for.
TLDR: There is a work-around. The boot code is looking for a filesystem label. Only took half a day of head-banging and navy language…
I edited both grub.conf and BOOT.conf (don’t know which did the trick) and replaced the CDLABEL with something I could name the flash drive from within Windows. “FEDORA32” in this case. Was able to boot a FAT32 flash drive live and Fedora seems happy.
Lines that looked like
linuxefi /images/pxeboot/vmlinuz root=live:CDLABEL=Fedora-WS-Live-32-1-6 rd.live.image rd.live.check quiet
Now read
linuxefi /images/pxeboot/vmlinuz root=live:CDLABEL=FEDORA32 rd.live.image rd.live.check quiet
Haven’t gotten to actually testing ISO loop booting or much else. Posting this on the off chance it helps others give live Fedora try.