So if you are new and getting into Rasbperry pi computers like me, you will find yourself getting errors or something goes wrong, and the article or book doesn’t mention these problems.
I ran into one of these when trying to build my own network server using a 2tb usb drive, and followed an article to the end, I rebooted and ended up in “emergency mode” in root.
so after freaking out and trying anything and everything I came across a post by, Leonid Shevtsov on his blog, He talks about if you have usb drives in your /etc/fstab and you boot into this emergency mode, go and comment # out that line. For me this was the fix I needed.
So if you find yourself in emergency mode, then just use nano and # out that usb drive