Beaglebone black dead or alive ?

I can no longer connect to the BBB via ssh (via eth0 or usb).
With a screen and a external keyborad, the screen remains black indefinitely with a flashing prompt at the top left of the screen.

Yet, the BBB seems to be alive. At the boot:
LED_D0 => Flashing
LED_D2 => Flashing slighty
LED_D3 => Flashing just at startup and turns OFF after a while.
LED_POWER => Steady ON
I had just modified the /etc/fstab file (dev/sda1 /media/usb/ vfat dmask=000,fmask=0111,user,sync,auto,nofail 0 0) so that a USB key was permently mounted. I did a reboot and nothing more, my problem appeared.

Do you think this could have a link ?
I a working on a emmc flash memory.
Do you think re-flashing the BBB can work ? and is this the solution ?
I would like not to lose everything.


Have you got a serial console cable ? Really need to see what is going wrong.

Probably reflashing the emmc would fix the issue, or just boot from an SD card image and fix whatever is causing the issue without having to reflash.

1 Like

i’ve seen similar issues after modifying fstab, if your booting from sd card, put your sd card in you desktop machine and comment out you fstab changes
if your booting from emmc, get a working sd card and boot the system with it, then mount emmc and edit the fstab in emmc, commenting out the changes.
hope this helps.
for future reference, after making changes to fstab, do a sudo mount -a, if things don’t work, ya can go back into fstab and make changes. just don’t reboot until things work.

1 Like

I dont have an answer to your question,

But you should be able to fix this without losing everything. Just stick your SD card into a Linux machine and edit the fstab file. Then put the SD card back into the BBB and it should boot

1 Like

Thank you for your answers, my problem is solved.
I connected to the serial console (connector J1) and I got the following message:

[ 24.642066] systemd[1]: Failed to mount /media/usb/vfat.
[FAILED] Failed to mount /media/usb/vfat.
[DEPEND] Dependency failed for Local File Systems.
You are in emergency mode. After logging in, type “journalctl -xb” to view
system logs, “systemctl reboot” to reboot, “systemctl default” or “exit”
to boot into default mode.
Give root password for maintenance
(or press Control-D to continue): [ 34.976775] davinci-mcasp 48038000.mcasp: IRQ common not found

I was able to open a session and comment the line in the /etc/fstab file: “dev/sda1 /media/usb/ vfat dmask=000,fmask=0111,user,sync,auto,nofail 0 0”
After a reboot everything returned to normal.
For information my problem was due to the fact that I had forgotten the space between /media/usb and vfat and I paid cash for it.
Thank you for your suggestions to resolve the problem.