nRF9160-DK , Modem_shell demo , ppp unable to access the Internet

[JackyChen]

Hello,guys

I build nrf9160-dk modem_shell demo as cmd '$ west build -b nrf9160dk_nrf9160ns ' and then '$ west flash ', after the system running up, I try to ping baidu website，it works as follow picture.

And then I rebuild the Modem_shell demo with cmd ' $ west build -p -b nrf9160dk_nrf9160_ns -d build -- -DOVERLAY_CONFIG=overlay-ppp.conf' for supporting ppp function. After the system running up, I try to ping baidu website again，it works as follow picture and it work failed.

I can capture any data from another serial, I guess VCOM0 serial is shell and VCOM2 serial is ppp channel.

To test my guess，I plugged nrf9160-DK board into my Ubuntu virtual machine and disable Ubuntu network. Use minicom tool to connect VCOM0 and open nrf9160-DK shell in A terminal, set the custom configuration for PPP uart with cmd 'ppp uartconf -b 115200' . New B terminal for ppp connection , type cmd ' $sudo pppd -detach /dev/ttyACM2 115200 DK-ip:Ubuntu-ip noauth nocrtscts local ' , then A terminal return "Dial up connection up" . New C terminal and type cmd ' ifconfig ' , I can see ppp0 and it's ip ,I try to ping baidu website,it work as follow picture.

it can't access the Internet ? why ? Did I operate wrong? Please point out my mistakes.

The version of modem_fw I use is 1.3.0 , ncs version is 1.7.0.

[Håkon Alseth]

Hi,

 

You are unfortunately running into a known issue with NCS v1.7.0:

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/known_issues.html?v=v1-7-0#other-issues

 

Issue is described here:

https://github.com/zephyrproject-rtos/zephyr/issues/38516

 

While a fixed is posted in this PR:

https://github.com/zephyrproject-rtos/zephyr/pull/38517

 

Could you try applying the above PR and see if it works better on your end?

 

Kind regards,

Håkon

[JackyChen]

Hello Håkon, thanks for your technical support.

yep, I merge this commit

https://github.com/zephyrproject-rtos/zephyr/pull/38517/commits/4ecaebf2b04fd48a1def8f8adf7bd3cc1528c482

and do the experiment again. Unfortunately, my VM-Ubuntu unable to access the network, it still doesn't work.

Best wish.

Jackychen

[JackyChen]

Just like this?

It looks like it got the DNS.

So, Should I type AT cmd  "AT%XEPCO=0"  to the modem_shell that I previously ran ,if I using modem_shell demo?

Thanks~

JackyChen

[Håkon Alseth]

Hi,

 

JackyChen said:

It looks like it got the DNS.

Yes, that is great!

JackyChen said:

So, Should I type AT cmd  "AT%XEPCO=0"  to the modem_shell that I previously ran ,if I using modem_shell demo?

Yes, that is correct.

 

Kind regards,

Håkon

[JackyChen]

Yep, I do what I said before, the result is like this:

the DK board can get the dns and I can ping www. website, but I try to connect the DK board with ppp on the other terminal, it failed.

What should I do next?

Thanks~

JackeyChen

[JackyChen]

I try reset,  power on and Off the dk-board again, change the computer, it fail too.

Thanks~

JackyChen

[Håkon Alseth]

Hi,

 

The DNS and ping seems to work fine, but the PPP connection seems to be not functional.

Can you try to let it assign IP automatically, ie. do not specify it directly? It seems that you've tried several of these settings before, but I'm unsure which you've connected to when trying to ping.

sudo pppd -detach /dev/ttyACM0 115200 noauth nocrtscts local

 

Kind regards,

Håkon

[JackyChen]

emmm...  I have tried to type cmd "sudo pppd -detach /dev/ttyACM0 115200 noauth nocrtscts local" ,  but it unable to connect DK-board by ppp, it show 

，

and the DK-board didn't react at all.

Thanks~

JackyChen

[Håkon Alseth]

Did you issue "ppp up" in the terminal before attaching with "pppd ..." on the PC side?

 

Kind regards,

Håkon

[JackyChen]

No... because I change the computer to try, but I get the same result...

[Håkon Alseth]

Hi,

 

Could you try issuing "ppp up" before attaching via pppd?

It should print the following afterwards in the uart terminal:

mosh:~$ ppp up
modem data socket 4 created for modem data
PPP data socket 5 created
PPP net if up.

 

Kind regards,

Håkon

[JackyChen]

Oh, I forget "ppp up"...

Now I enter “ppp up” and then "pppd ..." ,  ppp0 still no working in the PC...

I