Thanks!
So I asked everyone on the team whether someone has this revision RPi 4. Since it may take some time to find one, can you please try the above experiment I described, so that we see what a fresh OS image reports without the modem attached. We need to narrow down the issue more and more to see where the problem is.
Thanks,
Zahari
Actually instead of a device I was pointed to this issue: https://github.com/balena-os/balena-raspberrypi/issues/493
It looks like there is indeed a problem with the USB controller on those RPi 4 8GB models. Our devices team is investigating that, though no ETA on this yet. Please follow that GH issue for updates.
I see, thanks for the investigation!
This is a major concern for us, we’re about to start a POC with balena on Rpi4 8GB devices, and we cannot do it without modems 
Can you please confirm that on RPi4 4GB it works fine?
Also, I do not have access to the support thread,
how can I get updates regarding the progress, and estimated time for a fix?
Thanks!
Vitaliy
Hi Vitaliy,
We’ll do some checking re: the RPi4 4G. In the meantime, you should be able to track this forum thread at Configuring cellular modem with balena and the issue thread at https://github.com/balena-os/balena-raspberrypi/issues/493/.
John
Thanks John,
In the meantime we’re testing the same issue on RPi3 B+.
Now it looks much better!
We see modem’s devices being mapped to /dev/ttyACM*.
However, connectivity is still not working,
mmcli -L
returns:
error: couldn’t find the ModemManager process in the bus
issuing:
mmcli -m 0
returns:
error: couldn’t find modem at ‘/org/freedesktop/ModemManager1/Modem/0’
Please advise,
Vitaliy
Hi Vitaliy,
Can you re-enable support access for the device?
John
Hello,
In order to communicate with the hostOS dbus bus, you will need to add the io.balena.features.dbus label in for your container in docker-compose.yml and use DBUS_SYSTEM_BUS_ADDRESS=unix:path=/host/run/dbus/system_bus_socket mmcli -L
See https://www.balena.io/docs/learn/develop/runtime/#dbus-communication-with-host-os
Sure, granted.
Hi Vtialiy, did you try doing what Alexis suggested, that is, enabling DBUS? Try that and let us know if it works for you afterwards.
We just finished initial testing, looks great so far on RPi3!
Thanks a lot for your help!!
We still have the original issue with RPi4 8GB…
As mentioned earlier in the thread, this is likely due to https://github.com/balena-os/balena-raspberrypi/issues/493/ and once it’s resolved we’ll get back to you, so you can try the modem again.
Yes, I understand, Thanks a lot for your help!
Please let me know if you still need access to the RPi4 8GB device.
I think we are fine, thanks for cooperating Have a nice day!
1 Like
Hi there, we would like to inform you that the issue https://github.com/balena-os/balena-raspberrypi/issues/493 has been closed. You can now try the modem again
Great, thanks for the update!