first time post. I am a fellow noob. I wanted to boot my RPI4 from a usb 3.0 ssd drive AND not have the rpi4 continue to read the sd card. I followed the instruction in one of the answers to the following post:
The answer was to image both the SD card and SSD with the ubuntu image. I did that and I was able to boot. I verified on the command line:
ubuntu@ubuntu:~$ findmnt -n -o SOURCE /
and the result was showing that my dev/sda1 was the source.
I rebooted and verified again, but this time it showed the drive path of my SD card. I was confused because, immediately before, it asked me to change my password like the first time you boot.
So I repeated rebooting and each time I reboot, it alternates where it boots from (or the result from using "findmnt -n -o SOURCE /"). Interesting notes: no more password change request; the ip address to ssh kept alternating as well between the same two addresses in my router's network. sudo apt-get and all other commands seem to work.
How do I make it always boot from the SSD? Is this the reason why the RPI foundation claims the firmware doesn't support it? I read somewhere that the rpi4's firmware doesn't support booting from an external drive, but this method seems to work, at least while alternating where it boots from.
I'm not sure if I should have even attempted to use Ubuntu on RPI rather than sticking with Raspbian, but I would greatly appreciate a solution to my problem.
I also welcome resources for other matters. I am very noob to raspberry pi, the linux world, computer programming, etc. The extent of my computer knowledge is limited and along the lines of a gamer from MS Dos days to building my first computer in 2014.