DNS issues when roaming when using multi-IMSI SIM

RE: DNS issues when roaming when using multi-IMSI SIM

RileyH — Thu, 04 May 2023 16:02:41 GMT

Thank you for the response. You may close the case (I'm not sure if I can do that).

RE: DNS issues when roaming when using multi-IMSI SIM

Michal — Thu, 04 May 2023 11:38:20 GMT

There are 4 retransmissions for DNS. Timeout for 1st re-transmission is 1s and 3s for the others.

This is a modem feature and cannot be controlled from the application.

Best regards,

Michal

RE: DNS issues when roaming when using multi-IMSI SIM

Michal — Mon, 01 May 2023 15:44:23 GMT

Okay, I will check that with the experts.

Best regards,

Michal

RE: DNS issues when roaming when using multi-IMSI SIM

RileyH — Fri, 21 Apr 2023 15:32:56 GMT

Hi -

I am unable to provide a modem log at this for 2 reasons:

a) We are not able to duplicate the issue in our lab test bed (only in the field where it's difficult to obtain logs)

b) We need to do some work to enable modem logging but it's on the To Do list.

Can you tell me by inspection of Nordic code, what is the timeout of DNS requests in the offloaded sockets implementation? I am curious if it's set very short for longer latency requests.

RE: DNS issues when roaming when using multi-IMSI SIM

Michal — Wed, 19 Apr 2023 13:37:55 GMT

Hello,

Are you able to provide a modem log on that issue by chance?
Does this happen constantly after those several weeks of operation?

Best regards,

Michal

RE: DNS issues when roaming when using multi-IMSI SIM

RileyH — Wed, 19 Apr 2023 04:29:01 GMT

Hi, any update on this?

RE: DNS issues when roaming when using multi-IMSI SIM

RileyH — Thu, 13 Apr 2023 16:29:56 GMT

We are using modem firmware version 1.3.1 and SDK version 1.9.0

I was guessing that the code for the offloaded sockets was in binary only and perhaps resides in the modem firmware. I couldn't figure out how those symbols got resolved for the linker but obviously you guys do.

I am wondering if I should use the standard networking sockets stack instead of the offloaded version. Is there any documentation on pros and cons of either implementation?

I am also wondering if the our code calls aws_iot_connect() multiple times, would the AWS code also perform multiple DNS requests ? I am looking to see if we have a bug in our application where multiple aws_iot_connects() are called when trying to restore service after a disconnect.

If aws_iot_connect() statefull then I wouldn't expect multiple DNS requests to be performed.

RE: DNS issues when roaming when using multi-IMSI SIM

Michal — Thu, 13 Apr 2023 13:29:16 GMT

Hello,

Could you tell me the modem FW version as well?

I am consulting the experts on the main question currently, but I can answer question 3) now at least:

[quote user=""]3) Maybe a dumb question but why I can't find the source for nrf_getaddrinfo() ? I see the calls to it from nrf91_sockets.c but I can't find the source for nrf_getaddrinfo. [/quote]

It is a part of the modem library which is only distributed as a closed-source compiled library.

Best regards,

Michal

RE: DNS issues when roaming when using multi-IMSI SIM

RileyH — Tue, 04 Apr 2023 16:03:31 GMT

It's too bad that the SME wasn't able to comment on this ticket before going OoO. We have lost a week on this issue that is impacting our field trials and deployment. I ask that when the Engineer returns from OoO that he/she look at the question ASAP.

Thanks

RE: DNS issues when roaming when using multi-IMSI SIM

Michal — Tue, 04 Apr 2023 03:11:22 GMT

Due to holiday season (Easter) in Norway, we are a bit low in staff. The expert who could answer this is OoO and will be back after Easter. Sorry for the delays and thanks for your patience in advance. Happy Easter.