NRF9160 DNS resolution issue

RE: NRF9160 DNS resolution issue

Didrik Rokhaug — Tue, 08 Dec 2020 09:29:19 GMT

Yes, it is %XEPCO, my apologies.

EAI_SYSTEM does not give much information in itself. Instead, it instructs you to check errno, to get the "real" error code.

RE: NRF9160 DNS resolution issue

Aswin P V — Tue, 08 Dec 2020 09:14:40 GMT

We are using the Nb-IoT network.

We will try the XPCO command, just to confirm is it XPCO or XEPCO as i can see one more command in AT manual.

DNS_EAI_SYSTEM is the error code getting for getaddrinfo() function

RE: NRF9160 DNS resolution issue

Didrik Rokhaug — Mon, 07 Dec 2020 13:39:18 GMT

Hi,

Are you using LTE-M or NB-IoT?

If you are using NB-IoT, you can try to disable ePCO either with the %XPCO AT command, or by setting CONFIG_LTE_LEGACY_PCO_MODE=y in prj.conf (if you are building with SES, you must re-open the project or use 'Project->Run CMake...' for the change to take effect).

That has solved some DNS related issues in other networks.

If that does not help, can you print the value of errno?

But, to debug this properly, I would probably end up needing a modem trace. Can you capture one showing the error?

You can set the DNS server with nrf_setdnsaddr in NCS v1.2.0 and newer.

Best regards,

Didrik