I'm trying to set up a multi-ISO bootable USB using GRUB, but I'm hitting a wall. Most guides I've found are either outdated or tailored to specific Linux distributions, which isn't helpful for my situation. I've spent hours going through the GRUB manual, but I'm still lost.
Here's what I know: most distro ISOs are hybrid, so ideally, I shouldn't need to tweak much in GRUB since they have their own booting systems. I'm new to Linux, so I might be making some incorrect assumptions.
The ISOs utilize the iso9660 filesystem and come with their own grub.cfg files that manage BIOS/UEFI detections. What I'm struggling with is how exactly to instruct my GRUB installer to load these ISOs and boot them. Here's my current GRUB menu entry for reference:
menuentry "Fedora-KDE-Desktop-Live-43-1.6.x86_64" {
insmod iso9660
set isofile="/boot/iso/Fedora-KDE-Desktop-Live-43-1.6.x86_64.iso"
loopback iso $isofile
chainloader (iso)/
}
I really want to avoid suggestions like 'casper' or copying over vmlinuz and initrd, because they haven't worked for me in the past and don't seem like the right approach. My thinking is that an ISO is an optical disc image, so I should just be able to tell GRUB to load it as such, instead of hunting down kernel paths which seem to vary between distributions. What's the simplest way to have GRUB boot the ISO directly? Any tips would be appreciated!
3 Answers
You might want to check out Ventoy. It's pretty straightforward! Just prepare a USB stick with Ventoy, and then you can copy any ISOs you want directly onto that stick. After setting it up, it can boot any ISO you drop onto it without extra configuration. Plus, it's open-source, so you can modify it to fit your needs. Really saves a lot of time!
Ventoy is definitely the way to go for most use cases. It's hassle-free and works cross-platform, so you can use it on different devices without issues. I used to have trouble with manual setups, but Ventoy simplifies booting multiple ISOs. Just keep in mind that some images might have specific requirements, but it usually works like a charm!
I totally understand your frustration with trying to set this up manually. Documentation can be vague, especially regarding order and context. While Ventoy is a good option, if you're determined to learn GRUB, keep experimenting with your menu entries. It takes a bit of trial and error but once you get the hang of it, it's pretty satisfying! Good luck!
Yup, I'm in the same boat. The manuals are often confusing and lacking practical examples. Let’s keep sharing our findings, and maybe we can crack this together!
I agree with you on Ventoy. It might feel like you're skipping out on learning GRUB, but it's such an efficient solution for booting ISOs. If you're only looking for ease of use, it’s hard to argue against it.