Collection of several configs and command snippets to make our Raspberry Pi 3 B boot with a X3pro Black 2-USB3.1 250GB SSD.
Since the bootloader does not recognize the USB SSD, run bootloader, kernel+dtb from SD card, everything else from SSD. Mount SD card to /boot to receive dtb/kernel updates as usual.
write Raspbian image to SSD
remove boot partition (e.g. via gparted) to prevent partuuid confusion
resize service makes SSD boot scenario fail, so remove it from SSD:
rm /etc/init.d/resize2fs_once rm /etc/rc3.d/S01resize2fs_once
check if cmdline.txt on SD card needs adaption, see cmdline.txt for a working version in this repo (mainly increase loglevel)
use /etc/fstab from this repo (UUID points to SD card for /boot)
resize remaining partition to maximum size (e.g. via gparted)
- write Raspbian image to SSD
- remove all partitions but "boot" from SD
- resize remaining partition, so there is no unallocated space present after (e.g. via gparted)
- enable_uart=1 in config.txt for debugging