Take a look at the IODD ST400.

It's a hardware solution to your problem: you put multiple isos on an ssd, plug your ssd into the ST400, then plug the ST400 into the computer you want to live boot from (through USB).

From the ST400 you can quickly swap the active ISO, and it acts like a virtual DVD drive to the target computer, and you're basically ejecting and inserting a new DVD every time you do so.

You can also mount it for RW operations (ie. for inserting new ISOs without having to remove the SSD), for which it acts like a regular usb disk - but I recommend using it usually in RO mode to avoid data corruption.

It's not that user friendly, but once you get used to it, it's a perfect multiboot tool to have in your belt.

Also… I am not the most comfortable with downloading anything from Sourceforge these days.

Fair enough. You can download the iso from Github.

Though I haven't tried it, Yumi might be what you're looking for.

I tried to solve these cross-distro compatibility problems in a generic way with this "standard", more years ago than I'd like to think about:

https://www.supergrubdisk.org/wiki/Loopback.cfg

If someone wants to come up with a bootloader agnostic solution rather than one tied to grub, like an extension to Bootloader spec , https://www.freedesktop.org/wiki/Specifications/BootLoaderSpec/ , I'd be happy to evangelize it and add support to grub for using it.

I'm not aware of any other bootloader that supports reading a config file that exists within an iso though, and secure boot support may add additional complications.

Bottom line:

I feel like we could relatively easily get to a point where every Live iso that actually supports loop booting can just be added, as a file, to your USB drive (from Windows, or your android phone even) and be detected at boot in a nice little menu, no editing of config files needed.

I don't have the time or spoons to get the Linux community there alone, but if people are interested in helping I'm more than happy to pick this up again.

(Note: Please don't blindly suggest "Just chain load the iso!" Things aren't that easy, unfortunately).

Not sure if it fits what you're looking for but I usually use YUMI for multi boot situations, can't recall it giving me any issues over the years. But I don't do anything overly complex either.

Never had the need to use Ventoy myself so can't really give a good comparison but maybe others have used both & can give a better review.

PS - For what it's worth my basic toolkit is YUMI with https://www.system-rescue.org and https://www.memtest.org, that alone covers the vast majority of my diagnostics/rescue situations. But I've also added Windows 10 ISO onto the multi boot on occasion which could be useful for getting to a Windows prompt with Windows tools when needed - though I have a habit of keeping Windows on its own USB via https://rufus.ie

If you have some spare cash you can look at IODD or Zalman (white label iodd) devices. USB disk drives that also emulate an optical disk drive and mount ISOs.

I bought a Zalman back over a decade ago, still have and use it to this day. Used the daily in at data centres. Bees knees. Looking at the IODD devices now for the USBC port, but the Zalman is still working flawlessly.

https://alternativeto.net/feature/create-multiboot-usb/ Maybe this will help?

It's a common problem of all universal iso bootloaders. They make some kind of magic to boot images the way they are not supposed to. It breaks very often.

If you need a live system for diagnostics, simply install your favorite distro and tools that you use to a USB stick. And buy a second one for an installation image.

Gut feeling: Nope.

Further reflection, for those who remember a certain video game in the CGA error (not V, C)

“Here’s tae us, who’s like us, damn few, and they’re all dead. “

It just freakin’ works, which is a real benefit in our world.