nRF9160 Vodafone SIM DNS resolve not working and no COAP response received

[Willem21]

Dir Sir/Madam,

With CoAP(UDP) i'm sending some data to the californium.eclipseprojects.io.
With a simpoint SIM my code works fine (Whire shark capture shows ACK on each CON message).
With a vodafone SIM with exactly the same code it doesn't work (DNS resolve fails with error -2 DNS_EAI_NONAME).
When I change the code to use the static IP address it still doesn't work with the vodafone SIM ("recv" returns -1 with errno 11 EAGAIN).
Whire shark capture doesn't show the ACK response. And sometimes show the ICMP message "Destination unreacheable").

4278.Vodafone DNS resolve fail.bin

6406.Vodafone DNS resolve fail.pcapng

1538.Vodafone static IP recv fail trace.bin

7573.Vodafone static IP recv fail.pcapng

The APN is set correctly to "5g.vodafone.iot" and double checked with the SIM card supplier.
Can you see something in the modem trace / captures why the vodafone SIM is not working?

APN: 5g.vodafone.iot
nRF9160DK PCA10090 1.1.0
Modem firmware: mfw_nrf9160_1.3.4.zip
NRF Connect SDK V2.2.0
Technology: LTE-M
Windows 11

With best regards,

Willem

[Frans Lutz]

For some Vodafone IoT simcards you only have access to IP address which are "allowed" in your account. Can you check if this is also the case with this card?

[eabase]

I want to add that for Vodafone provided SIM cards, the APN you need to specify depends on both the use case and the Device Management framework you intend to use (I.e. CoioteDM, nrF DM, Vodafone DM, etc.)

For a LTE-M, or IoT-NB from a public (and non-b2b) source, you need to use: dm.vodafone.iot.
For normal LTE with 5G connectivity (in your country), you need to use what you stated in OP.