https client connection problem

RE: https client connection problem

Didrik Rokhaug — Mon, 23 Mar 2020 10:28:10 GMT

No, the nRF Cloud CA certificate should not be necessary to run the https_client sample.

However, I can imagine that if the nRF Cloud certificate somehow got corrupted, and thereby corrupted the filesystem used to store the certificates, that might explain why re-writing the nRF Cloud certificate lets you run the https_client sample.

Anyway, good to hear that it is now working!

RE: https client connection problem

chapman — Mon, 23 Mar 2020 02:05:33 GMT

After I reload the certificate which is downloaded from nrf cloud. It can run properly in asset tracker example and https_client example. Does it mean that the nrf cloud certificate is required for https_client example?

RE: https client connection problem

Didrik Rokhaug — Wed, 18 Mar 2020 10:43:38 GMT

The problem seems to be related to the network.

Your trace shows that the connection gets reset during the TLS handshake, which in turn causes the connect to fail.

When looking further into the trace, I find several lines where the modem reports "No PLMN action allowed".

Can you try to read out the certificate that is written to the modem?

The AT command would be: AT%CMNG=2,42,0

Edit: Note that the modem must be disabled (CFUN=4) when sending the command

The output should match the CA certificate of google.com. If it does not, that would explain the error.

What SIM card are you using?

Are you using the same network (NB-IoT, and legacy PCO) and SIM card when running the asset_tracker sample?

Could you take a modem trace of that as well for me to compare?

RE: https client connection problem

Didrik Rokhaug — Tue, 17 Mar 2020 09:11:12 GMT

Thanks.

Looking at the trace, there is something going wrong during the TLS handshake. I am working with the modem team to figure out exactly what.

I will let you know when I have more information.

RE: https client connection problem

chapman — Fri, 13 Mar 2020 02:55:01 GMT

I have tried again with original certificate but it still got the same result.

connect() failed, err: 45

I am using NB-IoT with modem firmware version: mfw_nrf9160_1.1.1

Asset tracker is workable in our network.

I have set two things in project configuration: NB-Iot and Legacy PCO.

Modem trace is attached. Thank you.

devzone.nordicsemi.com/.../trace_2D00_2020_2D00_03_2D00_13T02_2D00_39_2D00_26.454Z.bin

RE: https client connection problem

Didrik Rokhaug — Thu, 12 Mar 2020 12:28:47 GMT

Hi.

The sample works for me without any modifications. As the sample comes with the necessary certificate, it should not be necessary to download a new certificate.

One check you can do is to see if the certificate you downloaded matches the one used by the sample by default.

Are you using LTE-M or NB-IoT?

What verion on the modem firmware are you using?

Have you been able to use other samples that use TCP/TLS on your network (e.g. the asset_tracker sample)?

Can you take a modem trace, to help me identify the problem?

If you do not know how to take a modem trace, you can follow this guide: https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/how-to-get-modem-trace-using-trace-collector-in-nrf-connect

Best regards,

Didrik

RE: https client connection problem

chapman — Thu, 12 Mar 2020 10:12:14 GMT

Hi ,

I also try download the cert from chrome browser at google.com which is saved as a .cer files. '

Then I convert it by openssl:

openssl x509 -in google.cer -inform der -outform pem -out google.pem

Then I add back double quotation and newline symbol for each line.

However, the result is same:


connect() failed, err: 45