SIM7600-GH LTE Setup failed in RPi4 with ubuntu 22.04

[BeigeXiang9]

Please excuse me if my question is so naïve, I'm new to raspberry pi, and I want to connect an SIM7600 module to my RPI4 to setup a ppp connection over the internet. I have connected this module and tried to test the configuration using mincom: here is the logs

Welcome to minicom 2.8 OPTIONS: I18n Port /dev/ttyUSB2, 12:49:13 Press CTRL-A Z for help on special keys OK +CPIN: READY OK +COPS: 0,0,"vodafone IT",7 OK

AT+CGDCONT? +CGDCONT: 1,"IP","web.omnitel.it","0.0.0.0",0,0,0,0 +CGDCONT: 2,"IPV4V6","IMS","0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0",0,0,0,0 OK

AT+CGPADDR +CGPADDR: 1,2.41.148.4 +CGPADDR: 2,0.0.0.0,0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0 OK

This is the ubuntu logs of the RPi4 Module:
sudo dmesg | grep ttyUSB [ 9.675206] usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB0 [ 9.708232] usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB1 [ 9.714012] usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB2 [ 9.715124] usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB3 [ 9.801088] usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB4

however, when I try to call gprs I receive the following message:
$ sudo pppd call gprs
ip a show ppp0 Device "ppp0" does not exist.

highly appreciate your help,

[fshamsfakhr]

what your asking does not have a clear answer, the issue could be due to different rasons. you need to go through them step by step. first you need to make sure that APN configuration is set correctly, then you need to setup the modem (simcard module), then active a new Bearer, then connect it using ppp and at the end Verify Network Connectivity. All under one condition that the ppp is installed and sopported on the module (ubuntu kernel must support the ppp).

Verify the modem is seen by ModemManager
sudo apt update && sudo apt install -y usb-modeswitch modemmanager network-manager ppp
sudo mmcli -L
You should see something like Found 1 modem: /org/freedesktop/ModemManager1/Modem/0. Note the modem index (e.g. 0).

Check SIM status and PIN
sudo mmcli -m 0

If it says SIM PIN: enabled and state: locked, you’ll need to enter the PIN:
sudo nmcli --ask connection up simtech_modem

→ it will prompt "PIN (gsm.pin):"

Create a NetworkManager GSM connection

sudo nmcli connection add
type gsm ifname "*"
con-name simtech_modem
apn web.omnitel.it

Bring it up
sudo nmcli connection up simtech_modem
nmcli device status

Look for a gsm or wwan0 interface in the “connected” state.

ping -c 4 8.8.8.8

---

That's it, you should check the connection and if it fails, provide the logs for further debugging the issue

[BeigeXiang9]

Thanks @fshamsfakhr for detailed answer, I tried your suggestions, however It looks like the APN configuration is not applied correctly, as the bearer still shows YOUR_APN instead of web.omnitel.it. Additionally, the bearer is not connected (connected: no).

so ping -c 4 8.8.8.8, fails

[fshamsfakhr]

hmmmm. Since the APN is not being applied correct, you can manually create a new bearer

sudo mmcli -m 0 --create-bearer='apn=web.omnitel.it,ip-type=ipv4'

This should create a new bearer with the correct APN. Check the list of bearers:

sudo mmcli -m 0

if you see the correct APN, then go ahead and activate the new bearer using its path (e.g. replace Bearer/2 with the correct path if necessary):

sudo mmcli -b 2 --connect
sudo mmcli -b 2

to avoid any issue you should delete the old bearer. If the new bearer works, delete the old bearer (e.g. Bearer/1):

sudo mmcli -m 0 --delete-bearer=1

now test the network connectivity using the new bearer:
ping -I wwan0 8.8.8.8 (make sure the write name is wwan0 . you can use ifconfig or ip -a)

[BeigeXiang9]

Great @fshamsfakhr. I was able to successfully active the bearer. I had also another problem which I forgot to active the modem:

udo nmcli --ask connection up simtech_modem
PIN code is needed for the mobile broadband device
PIN (gsm.pin): ••••
Connection successfully activated (D-Bus active path:/org/freedesktop/NetworkManager/ActiveConnection/4)