Can't use EP06-E properly with Pi 4 board

[SuperBoss9]

Hello All!

I'm a new user of OpenWRT and I'm trying to make it work with EP06-E USB modem. The modem is connected via a separated USB-hub with external power supply (without it sometimes disconnects due to low voltage). The modem works as a sharm with my PC laptop under windows. So, I'm pretty sure that the modem works. Also I work with two different cellular operators. So there is no problem with them.

But I can't set it up to work with OpenWRT and Raspberry. The problem is somewhere with Interfaces declaration or underlying drivers. I've tryed to use in different network modes:

1. QMI/PPP/Default
2. ECM
3. MBIM

With no success. It seems (via web-panel or ifconfig via ssh) that OpenWRT tryes to set up an interface but then resets it or falls with an error. Sometimes it manage to obtain IP-address, but just after that drops interface and start the work from the scratch.

At the same time ordinary USB modems with DHCP interface works fine.

When the interface is dropping the modem itself is available via AT-commands and moreover it is connected to a LTE network. So it works.

Also I already did the trick with 3 seconds delay and killing of all QMI hang processes. Didn't help.

What can be wrong?

In System Log I see:

Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.487876] usb 1-1.3.3: new high-speed USB device number 8 using xhci_hcd
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.597303] usb 1-1.3.3: New USB device found, idVendor=2c7c, idProduct=0306, bcdDevice= 3.10
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.609093] usb 1-1.3.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.619815] usb 1-1.3.3: Product: EP06-E
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.626940] usb 1-1.3.3: Manufacturer: Quectel
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.634556] usb 1-1.3.3: SerialNumber: 0123456789ABCDEF
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.652510] option 1-1.3.3:1.0: GSM modem (1-port) converter detected
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.660700] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB0
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.669866] option 1-1.3.3:1.1: GSM modem (1-port) converter detected
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.678403] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB1
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.687623] option 1-1.3.3:1.2: GSM modem (1-port) converter detected
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.696888] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB2
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.706821] option 1-1.3.3:1.3: GSM modem (1-port) converter detected
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.715798] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB3
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.725720] qmi_wwan 1-1.3.3:1.4: cdc-wdm0: USB WDM device
Thu Dec 30 15:03:38 2021 kern.info kernel: [   43.733773] qmi_wwan 1-1.3.3:1.4 wwan0: register 'qmi_wwan' at usb-0000:01:00.0-1.3.3, WWAN/QMI device, e2:4e:8c:2d:33

and in Kernel log:

43.487876] usb 1-1.3.3: new high-speed USB device number 8 using xhci_hcd
[   43.597303] usb 1-1.3.3: New USB device found, idVendor=2c7c, idProduct=0306, bcdDevice= 3.10
[   43.609093] usb 1-1.3.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   43.619815] usb 1-1.3.3: Product: EP06-E
[   43.626940] usb 1-1.3.3: Manufacturer: Quectel
[   43.634556] usb 1-1.3.3: SerialNumber: 0123456789ABCDEF
[   43.652510] option 1-1.3.3:1.0: GSM modem (1-port) converter detected
[   43.660700] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB0
[   43.669866] option 1-1.3.3:1.1: GSM modem (1-port) converter detected
[   43.678403] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB1
[   43.687623] option 1-1.3.3:1.2: GSM modem (1-port) converter detected
[   43.696888] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB2
[   43.706821] option 1-1.3.3:1.3: GSM modem (1-port) converter detected
[   43.715798] usb 1-1.3.3: GSM modem (1-port) converter now attached to ttyUSB3
[   43.725720] qmi_wwan 1-1.3.3:1.4: cdc-wdm0: USB WDM device
[   43.733773] qmi_wwan 1-1.3.3:1.4 wwan0: register 'qmi_wwan' at usb-0000:01:00.0-1.3.3, WWAN/QMI device, e2:4e:8c:2d

It seems that the problem is somewhere in qmi.sh it can't launch DHCP interface for QMI modem. That may happen due some non-standard answer from EP06-e modem or some other mistake.

[SuperBoss9]

I did manage to make it work. The thing I did - carefully fell: APN, login/pass, IP-version, authentification version. After that it starts to work. Along QMI interfaces I started to notice also Virtual DHCP that works.

The only problem that remains - when I launch speedtest on this interfaces - the connection drops Under window there is no scuh a behaviour.

[SuperBoss9]

The problem wasn't in OpenWRT. The problem was in Beeline operator. When I changed the sim to MTS operator everything started to work well.