12-05-2019, 04:46 PM
(This post was last modified: 12-05-2019, 04:55 PM by Arglebargle.)
I'd like to note two things for people writing images:
First, add "conv=fsync" to your dd options -- this forces an fsync of the target device after dd is finished writing.
Second, on first boot both the Debian and Ubuntu images silently run a script that resizes the root filesystem to fill all remaining space on the sd/emmc storage they were written to. This can take several minutes (longer on slow sd cards!) during which time the screen will be blank. Don't interrupt this process by force-rebooting or you can damage the newly installed filesystem and render it unbootable. Yes, this probably should have some display output to tell the user something important is happening.
Edit, Bonus: You can compare/verify a flashed emmc/sd card with the image file you just dd'd onto it using the following to verify that the image was written without errors:
First, add "conv=fsync" to your dd options -- this forces an fsync of the target device after dd is finished writing.
Second, on first boot both the Debian and Ubuntu images silently run a script that resizes the root filesystem to fill all remaining space on the sd/emmc storage they were written to. This can take several minutes (longer on slow sd cards!) during which time the screen will be blank. Don't interrupt this process by force-rebooting or you can damage the newly installed filesystem and render it unbootable. Yes, this probably should have some display output to tell the user something important is happening.
Edit, Bonus: You can compare/verify a flashed emmc/sd card with the image file you just dd'd onto it using the following to verify that the image was written without errors:
Code:
</dev/mmcblkX head -c "$(stat -c %s my.img)" | cmp - my.img