Troubleshooting

sdm places important files in the IMG in /etc/sdm that are used to control its operation and log status.

• apt.log contains all the apt command output (package installs) done during the SD Card creation

• cparams contains the parameters with which sdm was initially run on the image

• history is the log written by sdm

• 1piboot.conf is the configuration file used when the IMG was customized

• auto-1piboot is used by sdm to implement settings that must be delayed until the FirstBoot service runs. See https://github.com/gitbls/sdm/wiki/First-Boot-Service

• custom.ized tells sdm that the image has been customized. If this exists, sdm will not rerun Phase 0 unless you answer Y to the query at the start of customization. You can avoid the prompt by including the --redo-customize switch on the command line.

Cleaning up dangling mounts

If something is not working right, make sure that there are no dangling mounts in the running RasPiOS system. You can end up with a dangling mount if sdm terminates abnormally, either with an error (please report!) or via an operator-induced termination. If sdm is not running, you should see no "/mnt/sdm" mounts (identified with `sudo df').

You can unmount them by manually using sudo umount -v /mnt/sdm/{boot,}. This will umount /mnt/sdm/boot and then /mnt/sdm. You'll need to delete the dangling loop device also.

Loop devices

A couple of quick notes on loop devices, which are used to mount the IMG file into the running system.

• losetup -a lists all in-use loop devices

• losetup -d /dev/loopX deletes the loop device /dev/loopX (e.g., /dev/loop0). You may need to do this to finish cleaning up from dangling mounts (which you do first, before deleting the loop device).

• If your system doesn't have enough loop devices, you can increase the number by adding max_loop=n on end of /boot/cmdline.txt and reboot.