I have to provision multiple Raspberry Pi's, and I thought I could simply copy one's memory card using dd to a file, and use that file to flash multiple new memory cards. I've tried this multiple times and it hasn't worked.
I'm planning on forking https://github.com/RPi-Distro/pi-gen and adding what I need using that, but I'm curious why my original approach didn't work. What is different about these files, the file I created using dd, vs. the Raspbian ISO file that I flash onto the memory card?
I'd also like to be clear and differentiate from a Live CD. I am copying the OS directly to the Pi's "harddrive" (the micro SD card) in both cases.
I created the image in an Ubuntu VirtualBox VM, with the Micro SD card mounted as a USB device into the VM
Originally posted on SO, someone over there suggested that I need to copy, or setup somehow, the master boot record.