Using getaddrinfo for DNS-Lookups (nrf9160 DK)

[ntv1000]

Hello!

I'm currently trying to run the mqtt_simple sample (latest version of nrf-zephyr) on the nrf9160 DK. Unfortunately it is not working, because getaddrinfo() returns 22 (EINVAL?).

I'm trying to run the sample using NB-IoT. For that I flashed the appropriate firmware (pre-alpha) and I'm also using an appropriate SIM-card. TCP connections alone (without getaddrinfo()) are working and I'm able to exchange data with a server over the internet.

Specifically the DNS-lookup with getaddrinfo() seems to run into trouble. I also tried to pass an IP-Address to getaddrinfo(). In that case it returns no error, but gives incomplete results (Address correct, but hints about e.g. socktype ignored).

My best guess would be that the nrf_getaddrinfo() implementation is incomplete here. I would be happy about any information about this.

[Hakon]

Hello, what is your location? Which ISP are you connecting to?

[ntv1000]

I'm in Austria and I have a SIM card from T-Mobile. I confirmed that the TCP connection itself is working.

[ntv1000]

Seriously? In the best case that would mean I will always be locked into whichever DNS server my provider wants me to use? In the worst case it means that DNS resolution doesn't work if the provider is doing something wrong as can be seen in this case. That seems like a basic feature to me for a released product. I'd highly suggest supporting this feature as soon as possible.

[Hakon]

ntv1000 said:

I'd highly suggest supporting this feature as soon as possible.

I have confirmed now that it will be available in a future release.

[ntv1000]

Is there any update available on the matter?

[Sigurd]

Hi,

ntv1000 said:

Is there any update available on the matter?

Yes, it will be supported in modem fw v1.0.0. This modem fw version will likely be released later this week.

[ntv1000]

Hello, thank you for implementing this, but I'm unable to flash this modem firmware since, according to the readme, I'm supposed to use the nRF Connect Programmer. Unfortunately that tool doesn't seem to support the nRF91 development board, yet. Firstly, the Github page doesn't list it under supported devices and secondly, when I try it anyway the programmer gets stuck at "Reading device non-volatile memory".

So how am I supposed to flash the new modem firmware then? I would also be happy using the old MDM DFU tool, but it doesn't seem to support a firmware image being split into multiple segments.

[miked531]

the modem flash utility is included in nRF connect v3.0.0. see https://devzone.nordicsemi.com/f/nordic-q-a/49264/unable-to-update-firmware-on-nrf9160

also note that the "update modem" button is in the bottom right, which in my case it took a while to find it since it was scrolled off the screen

[ntv1000]

Alright I got it working, I had the nRF Command Line Tools not installed on my system so I was just missing the nrfjprog binary. So it turns out the nRF Connect Programmer works with the nRF9160 despite the Github page not saying so.

So now my question is: How to use the newly implemented feature? I tried to set these configuration options:

CONFIG_DNS_RESOLVER=y
CONFIG_DNS_SERVER_IP_ADDRESSES=y
CONFIG_DNS_SERVER1="8.8.8.8"

It is still generating the error of the original post. I guess these configuration options only apply to the zephyr resolve library.

Is there perhaps an AT-command that is not documented yet? I'm looking at the AT Command Reference v1.0.