Dual boot with external SSD

[WesternSlope]

If I were to hook an external SSD drive to another laptop to install Mint then pull it out of the other laptop, move it to this system, and somehow point the boot to the external that has Mint?
Thanks

[rambo919]

It can work, but it all depends on the machine you are booting from.

And you will always bottleneck the SSD by your USB connection.

[Telyx]

I did that with my old work computer--installed Mint 20.1 MATE to an external SSD, making sure to install grub to that SSD too. I changed the BIOS boot order so the computer would look first to USB, then to the HDD. It worked pretty well--if I had the SSD plugged in, the computer booted to Mint, and if I didn't have it plugged in it booted Windows 7. (At least it was USB 3.0, so the bottleneck wasn't as bad as it could have been.)

[AndyMH]

Legacy or UEFI boot? With UEFI boot there is a bug in the installer when installing to a second drive, it won't put grub where you tell it. Relatively straightforward to fix.

[WesternSlope]

Legacy or UEFI boot? With UEFI boot there is a bug in the installer when installing to a second drive, it won't put grub where you tell it. Relatively straightforward to fix.

I was dreading the Intel Optane and RTS, but I think I have it figured out. I'll put the SSD on the inside and then install Mint.
Thanks all

[AndyMH]

I was dreading the Intel Optane and RTS, but I think I have it figured out. I'll put the SSD on the inside and then install Mint.
Thanks all

If you have UEFI boot you will end up with grub on the main system drive unless you do something about it. Then your external SSD will not boot independently. Doesn't matter whether you connect the SSD internally or externally.