LTE 4G - Roaming or Login issue

kuumaur · July 22, 2023, 12:51pm

Hi,
I have an issue with my 4G setup.
I am running openwrt on a TP-Link Archer C5 and on a Raspberry Pi(for backup reason).
My setup is running in germany quite well and stable.

But if I cross the border for example to denmark, the router do not establish a connection.
I have tested 2 different Sim Cards from 2 diff. Providers (O2 Max Prepaid and Telekom/Edeka).
Both Sim cards are prepaid.
Sometimes I get an Error: Unknown error (NETWORK_REGISTRATION_FAILED)
Sometimes I get an IP Address, but routing is not working
Sometimes I get no IP Address

When I plug the Sim Cards into my Smartphone, there is no issue.

Has someone ideas to narrow down that issue or where/what to look for?
Is it possible that the providers in denmark block router/non-Smartphone connections?

My LTE Modem is a ALFA Tube-U4G USB
It is used by QMI driver 1.30.8-1
OpenWrt Version 22.03.5
Kernel 5.10.176

kuumaur · July 26, 2023, 2:38pm

I have bought a Huawei E392. The Modem is working, but it does not register to a Network.
Is there a way to list and select a particular network provider?

AndrewZ · July 26, 2023, 4:45pm

Check with AT+COPS=? first.
For QMI modems you can set option plmn in configuration:

First three digits are the mcc (mobile country code) and the last three digits are the mnc (mobile network code), for example if plmn=338020, then the mcc is 338 and the mnc is 020

or manually with AT+COPS command, see AT commands guide for details.

EDIT:
Make sure that both "Use default gateway" and "Use DNS servers advertised by peer" are ticked in Advanced Settings and also the assigned firewall zone is WAN.

kuumaur · July 27, 2023, 7:09pm

I have set these options in config file:
config interface 'mobilenetwork'
option proto 'qmi'
option device '/dev/cdc-wdm0'
option pdptype 'ipv4v6'
option apn 'internet.t-mobile'
option plmn '238006'
option auth 'both'
option username 't-mobile'
option password 'tm'
option autoconnect '1'
option modes 'lte'

AndrewZ · July 27, 2023, 7:20pm

Now check if you're registered to this network:
uqmi -d /dev/cdc-wdm0 --get-serving-system
and connection status:
uqmi -d /dev/cdc-wdm0 --get-data-status

I suggest changing option pdptype 'ipv4v6' to option pdptype 'IP'

Please format the output using </> icon.

kuumaur · July 28, 2023, 7:15pm

Iam getting the following output:

root@pi1:~# uqmi -d /dev/cdc-wdm0 --get-serving-system
{
        "registration": "not_registered"
}

root@pi1:~# uqmi -d /dev/cdc-wdm0 --get-data-status
"disconnected"

I also changed to the O2 SIM Card:

root@pi1:~# uci show network.mobilenetwork
network.mobilenetwork=interface
network.mobilenetwork.proto='qmi'
network.mobilenetwork.device='/dev/cdc-wdm0'
network.mobilenetwork.plmn='238006'
network.mobilenetwork.autoconnect='1'
network.mobilenetwork.modes='lte'
network.mobilenetwork.apn='internet'
network.mobilenetwork.auth='pap'
network.mobilenetwork.peerdns='1'
network.mobilenetwork.dns='8.8.8.8'
network.mobilenetwork.pdptype='IP'
network.mobilenetwork.defaultroute='1'

, but still no luck. 238 should be denmark and 006 should be 3DK. This SIM is doing well, when I but it into my Smartphone. The only simelarity that I can see is, that both LTE Modems are Cat3. I dont know what Iam doing wrong.

AndrewZ · July 28, 2023, 7:32pm

This [second hand] E392 may have some bands disabled, so the modem cannot see the network(s).
Run

opkg update
opkg install picocom kmod-usb-serial-option

Access the modem with picocom /dev/ttyUSB0
Send the following commands to the modem and show results:

ATI
AT^VERSION?
AT^SYSINFOEX
AT^SYSCFGEX=?
AT^SYSCFGEX?

kuumaur · July 29, 2023, 2:33pm

Here is some output:

---SNIP---
AT+COPS=?
^RSSI:24

^RSSI:24

^RSSI:24

^RSSI:24

^RSSI:24

^RSSI:24

^RSSI:24

^RSSI:24

+COPS: (1,"3 DK","3 DK","23806",2),(1,"TDC","TDC","23801",0),(1,"TDC","TDC","23801",7),(1,"3 DK","3 DK","23806",7),(1,"","","23866",0),(1,"DK SONOFON","SONO","23802",7),(1,"TELIA DK","TELIA","23820",7),,(0,1,2,3,4),(0,1,2)

OK
---SNIP---
ATI
Manufacturer: Huawei Technologies Co., Ltd.
Model: E392
Revision: 11.335.31.01.07
IMEI: 860999002662031
+GCAP: +CGSM,+DS,+ES

OK
---SNIP---
AT^VERSION?
^VERSION:BDT:Nov 25 2011 15:53:31
^VERSION:EXTS:11.335.31.01.07
^VERSION:INTS:
^VERSION:EXTD:UTPS23.001.07.06.07_MAC23.001.07.05.07

^VERSION:INTD:UTPS23.001.07.06.07_MAC23.001.07.05.07

^VERSION:EXTH:E392CD1E392M Ver.C
^VERSION:INTH:E392u-12CD1E392M Ver.C
^VERSION:EXTU:E392
^VERSION:INTU:E392u-12
^VERSION:CFG:104
^VERSION:PRL:

OK
---SNIP---
AT^VERSION?
^VERSION:BDT:Nov 25 2011 15:53:31
^VERSION:EXTS:11.335.31.01.07
^VERSION:INTS:
^VERSION:EXTD:UTPS23.001.07.06.07_MAC23.001.07.05.07

^VERSION:INTD:UTPS23.001.07.06.07_MAC23.001.07.05.07

^VERSION:EXTH:E392CD1E392M Ver.C
^VERSION:INTH:E392u-12CD1E392M Ver.C
^VERSION:EXTU:E392
^VERSION:INTU:E392u-12
^VERSION:CFG:104
^VERSION:PRL:

OK
AT^SYSINFOEX
^SYSINFOEX:1,0,1,0,,3,"WCDMA",41,"WCDMA"

OK
---SNIP---
AT^SYSCFGEX=?
^SYSCFGEX:("00","03","02","01","99"),((2000001400380,"GSM900/GSM1800/WCDMA900/WCDMA2100/WCDMA1800"),(280000,"GSM850/GSM1900"),(3fffffff,"All Bands")),(0-2),(0-4),((800c5,"LTE2100/LTE2600/LTE1800/LTE900/LTEDD800"),(7fffffffffffffff,"All Bands"))

OK
---SNIP---
AT^SYSCFGEX?
^SYSCFGEX:"00",3FFFFFFF,1,1,7FFFFFFFFFFFFFFF

OK
---SNIP---
AT+CGDCONT?
+CGDCONT: 1,"IP","","0.0.0.0",0,0

OK
---SNIP---

Thanx for your help, I appreciate it.

kuumaur · July 29, 2023, 5:56pm

Ok, I switched back to my former ALFA Tube U4G (Quectel EC25). With modifications based on your suggestion, it is now working. The Huawei E392 is still not working connecting.
Thinks I noticed:
The Huawei only reported wcdma with --get-signal-info, which I suppose is 3g network. It might be, that here in denmark not all frequencies are covered, and the E392 Dongle does not have all the neccesary freq.
The Alfa Tube U4G is reporting lte with --get-signal-info.

root@pi1:~# uqmi -d /dev/cdc-wdm0 --get-serving-system
{
        "registration": "registered",
        "plmn_mcc": 238,
        "plmn_mnc": 6,
        "plmn_description": "3 DK",
        "roaming": true
}
root@pi1:~# uqmi -d /dev/cdc-wdm0 --get-data-status
"connected"
root@pi1:~# uqmi -d /dev/cdc-wdm0 --get-signal-info
{
        "type": "lte",
        "rssi": -74,
        "rsrq": -15,
        "rsrp": -103,
        "snr": 10.400000
}

Thank you very much for your patience and your knowledge.

kuumaur · July 29, 2023, 5:58pm

Another question I got just into my mind is, do I need to activate the lte mode in the Huawei E392 Dongle?

mk24 · July 29, 2023, 6:02pm

It's useful to test USB modem dongles with a desktop or laptop computer before trying to use with OpenWrt. The manufacturer may have Windows software to configure them.

AndrewZ · July 29, 2023, 7:00pm

Check with working Alfa modem:
uqmi -d /dev/cdc-wdm0 --get-cell-location-info | grep -w 'band\|frequency'

kuumaur · July 29, 2023, 7:19pm

Here is the output:

root@pi1:~# uqmi -d /dev/cdc-wdm0 --get-cell-location-info | grep -w 'band\|freq
uency'
		"band": 1,
		"frequency": 2100,

kuumaur · July 29, 2023, 7:23pm

If I am not too wrong, the Huawei E392 should support 2100 MHz for LTE.

AndrewZ · July 29, 2023, 7:39pm

B1 is supported by E392u-12 and it is currently configured to use all the bands (and all technologies - 2/3/4G) - ^SYSCFGEX:"00",3FFFFFFF,1,1,7FFFFFFFFFFFFFFF

Some ideas:

switch to another provider
force modem to 4G with AT^SYSCFGEX="03",3FFFFFFF,2,4,7FFFFFFFFFFFFFFF,,

AndrewZ · July 29, 2023, 8:19pm

That does not look right as APN is missing. I would put there something like this:
AT+CGDCONT=1,"IP","internet","0.0.0.0",0,0

kuumaur · July 30, 2023, 6:17pm

Hi, I did not have any Internet connection today. Had to ride to the "Golden M" to get some Wifi connection.
The 4G connection is now working (since a few minutes) with the Huawei dongle and your AT-Syscfgex command.
Thanx again for your help.
I will mark this a the working solution.

system · August 9, 2023, 6:17pm

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