Internal ssd + external ssd security

[fsflover]

Hi @parmenides, welcome to the Community! It seems your questions is similar to the one answered below:

Security using qvm+windows?

If you use Qubes from the USB device and sometimes boot your main system from the hard drive, it might be equivalent to multibooting: Also, you don’t have a sys-usb, so you are not protected from malicious USB devices in this case.

In other words, it’s not as secure as using Qubes bare-metal. But it’s still much more secure than using anything else.