The Raspberry PI has become more and more powerful in the recent years, maybe too powerful to be a “maker board”. The higher CPU power and availability of more memory - up to 8GB - makes it more suitable for home server usage.
The latest firmware (EEPROM) enables booting from a USB device. To enable USB boot the EEPROM on the raspberry needs to be updated to the latest version and the bootloader that comes with the operating system - the start*.elf, etc files on the boot filesystem - needs to support it.
I always try to use filesystem encryption. You’ll find my journey to install GNU/Linux on an encrypted filesystem below.
64 Bits operating systems
The Raspberry PI 4 has a 64 bits CPU, the default operating system - Raspberry Pi OS (previously called Raspbian) - for the Rasberry PI is still 32 bits to take full advantage of the 64bits CPU a 64 bits operating system is required.
You’ll find an overview GNU/Linux distributions for RPI4 below.