Can't initiate ping in nRF9160 to one APN.

[olegtk1]

Hi.

In our private network we experience one problem.

We can ping Google (8.8.8.8) via APN customer4. In Wireshark traces it is seen that ping is initiated.

On RRC level Control plane service request is initiated, and ping is run successfully.

When we change APN to internet, we can see that ping is not initiated, UE turns into RRC-IDLE state after expiration of inactivity timer.

And we can see error-22 at terminal session.

Can somebody prompt what can be a reason for such fails?

Thanks,

Oleg

trace of At commands failed pings.pcapng

trace-customer4APN__AT_commands successful ping.pcapng

[Michal]

Hello Oleg,

What are your NCS and Modem FW versions?

Also, do you have the original .bin/.mtrace modem traces as well?

Best regards,

Michal

[olegtk1]

Hi Michal.

Thanks for Your response.

This is Modem FW version:

I am not sure if it is NCS:

I will ask Customer for original .bin/.mtrace .

We are planning another log collection session with Customer.

Would You suggest please if anything else is needed except Trace Collector logs?

BR

Oleg

[Michal]

Thank you and sorry for the delay.

That is a really old version of Modem Firmware (the newest is 1.3.5) and NCS (Zephyr 2.4.99 should be NCS version 1.5.x, the newest version is 2.5.0 with Zephyr version 3.4.99).

Unless it's an old existing project, I would recommend upgrading if possible.

They could also try to enable the network logs maybe?

CONFIG_NET_LOG=y

I am also asking our experts if they have any other tips, but it may be difficult to debug with such old SDK.

Best regards,

Michal

[Michal]

Just to reconfirm, our experts would like the raw/binary modem traces to be able to debug it more in-depth.

Best regards,

Michal

[olegtk1]

Hi Michal. I requested from our Customer raw/binary modem traces but they do not respond. We sent them our modem that we used for tests in ou Lab. Hope they will collect logs during tests with our modem.

I will  inform You as soon as I have any update.

Best Regards

Oleg

[Michal]

Hi Oleg,

Thank you for the information.

Best regards,

Michal

[olegtk1]

Hi Michal.

Customer upgraded modem firmware from FW version mfw_nr9160_1.2.7

to version mfw_nrf9160_1.3.5

And after this FW upgrade pings to APN internet run successfully:

Thank You. But, after this FW upgrade they were not able to collect Modem traces anymore.

Would You suggest if there is any way to enable trace collection?

Best Regards

Oleg Tkachenko

[Michal]

Hello Oleg,

Good to hear that the original issue got solved.

olegtk1 said:

Thank You. But, after this FW upgrade they were not able to collect Modem traces anymore.

Did they enable CONFIG_NRF_MODEM_LIB_TRACE after the update?

Best regards,

Michal

[olegtk1]

Hi Michal.

Can You share instructions how to do that?

BR

Oleg Tkachenko

[Michal]

Hi Oleg,

They just have to add CONFIG_NRF_MODEM_LIB_TRACE=y to their prj.conf file.

Also, if they flash the Modem Shell sample from Cellular Monitor then it should have traces enabled by default as well.

Here is a blogpost about Cellular Monitor if needed:  Introducing the Cellular Monitor

Best regards,

Michal

[olegtk1]

Hi Michal.

Thank You ! I will pass this ino to Customer.

Would You please guide me on another issue. 

I met in Internet results of PING testing nRF9160 DK in India.

Here is the link: Testing NB-IoT connectivity in India with NRF9160 and Airtel - Electronic Projects Design/Ideas - Electronics-Lab.com Community

They run ping directly via AT commands. In nRF9169 DK AT COMMANDS pdf I was not able to find AT PING command.

But, according to below screenshot Indian colleagues pinged Google with AT command successfully:

 Due to the low resolution of the image, I can't make out the command.

Was it  ">AT%PING="www.google.com",45,5000,5,1000"?

Should ">AT%PING=xxx " work? In case if I do not want to make it via Modem Shell?

BR

Oleg Tkachenko

[Michal]

Hello Oleg

That is the AT#XPING command from SLM.

Best regards,

Michal