Multi-boot USB that doesnt require CSM on or Secure-boot off?

I presume this doesnt exist - at least I havent found it in my digging. I dont want to enable CSM, or have to bother with disabling secureboot, even though it would admittedly make a few things easier.

I just ran into a situation where I dont have enough usb sticks for what I need. That and finding it a bit silly to use up an entire 64gb usb stick for a rescue environment amounting to megabytes, had me look into my options.

Initially i thought I could partition a drive, add drive letters to each partition, and call it a day. Apparently in a perfect world - just not this one.

So I then saw the multitude of multiboot offerings, winsetupfromusb, yumi, easy2boot.

Seems each and every one requires secureboot to be disabled, CSM to be enabled, or both.

Ideally id have a linux, mac, and windows installer all on the same flash. I can see where that becomes sketchy due to the mac filesystem. Its possible but a doozy iirc.

I'm willing to split my installers up on separate sticks, but i'd like to at least get my rescue environments on the same one. Macrium/WindowsRE/MinitoolPW. Perhaps add memtest.

is that possible given the constraints?

Kyhi, on a UEFI multi boot don't you need to turn off secure boot? Some of the boot loaders may not be digitally signed.

so what your saying is, if im fat32 im in the clear?

I imagine this is feasible barring one small tidbit. If i wanted to add windows install media (if i wanted to get EVERYTHING on one usb) it would be impossible as fat32 as i believe fat32 limits you to 4gb files and the win10 installer is >4gb i "think"

also, why do all these frontends (easy2boot is the main one im looking at) say secureboot must be disabled?

Just trying to pick my battles ahead of time before i spend an absurd amount of time throwing my face at something thats purely QoL for the most part. With two toddlers, i value my free time TREMENDOUSLY lol.

thanks for your replies.

Kyhi said:

We are Using The Windows Boot Loader....
All we need to do is Add Entries Into the existing BCD - pointing to different Folders w/ a Discription
Sources/Boot.wim
WindowsSetup/Boot.wim
MacruimReflect/Boot.wim
Win10XPE/Boot.wim
MiniTool/Boot.wim

With the above example the USB would Boot and the Boot Menu ( BCD ) would list 4 Boot Options...
Just Like your Host PC does with a Multi-Boot Configuration..

Thus when you boot from USB a Boot Menu is Displayed with The Different Software Boot Option...

It is just a matter of editing the Boot Menu(s) on the USB Stick

Care to point me to some information, or give me a rough (less rough) run-through on how this can be done?

As noted, im absolutely okay with having to keep my windows/linux/mac installers on separate usb sticks. I have enough for that. I gather smashing windows & linux on one is substantially easier than also including osx and id just get annoyed by having 2 on 1 and having to keep another on its lonesome lol.

Would love to get the listed recovery environments and memtest all on one stick thats bootable from my main pc's which use UEFI & secureboot with CSM disabled, and my laptop which is Bios/mbr (original C2Duo in that bad boy lol)

this would be the preferred method then? as opposed to using one of the other boot loaders? Using the windows boot loader would require the windows install to be present or just part of it? like the winre.wim?

would be able to use this on a pc that doesnt have windows itself installed yet right?

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Berton said:

Two things, I've never had success installing Windows natively on a removable drive, doesn't like it, and along with the 4GB [plus or minus 1 Byte] single-file-size limit of FAT32 there is also the Windows limit of 32GB partition size of FAT32. I have formatted HDDs as FAT32 up to 500GB in size but it requires using a version of Linux with the GPARTED program or the GPARTED LiveCD to do it and Windows can use that.

Ive installed all my windows installs (that i can recall) from removable drives, but i think they were partitioned as ntfs? Its been a looooong time ive been running the same installs. (#hugs macrium)

i was a bit caught up on being forced to use fat32 in this instance myself, but its the only way without getting crazy with a third party bootloader which comes with the stipulations that im posting about.

Berton said:

Storing the installation files on external drives is quite different from installing to external drives. Only ones I've had success with have been with a few 'flavors' of Linux [using Mint 19.3 on a Desktop and 2 Notebooks now], has a Disk Imager/Writer application to create a bootable USB drive while it is running but the source file/.iso has to be downloaded and available. My MacBook Pro with OS X died while trying to Upgrade to macOS, it was 9 years old and not cost-effective to repair [drive controller on the motherboard failed].

oooh i misread. installing TO external drives. Apologies :P