I'm running a 2012 MBP with a 500GB SSD and a 750GB 2.5" spinner in the DVD bay. I have OS boot drives for both Mojave and Catalina on the SSD, and clones for both on the HDD. I use File Vault encryption on all the bootable volumes. Every time I boot, it asks the questioned for all the other bootable drives. see attached below. Since I don't really want them mounted, I just cancel, but I have to do this up to five times, since Catalina asks for the password for both the system folder and the data folder. Or do I just need to download N*0*0*M?
I believe I need to encrypt every boot volume to protect the data? Is there anyway to fix this?