https_client returning "getaddrinfo() failed, err 9"

[Saketaram]

I am based in Hong Kong. I purchased NB-IoT sim card with "Three". 

When using LTE Link Monitor, (with at_client) I can connect to the NB_IoT network, as Three support told me they can see my sim connected.

When I try https_client sample, I get "getaddrinfo() failed, err 9"

I changed prj.conf to cope with NB-IoT, rather than the standard LTE-M at boot:

CONFIG_BSD_LIBRARY=y
CONFIG_BSD_LIBRARY_SYS_INIT=n

CONFIG_NETWORKING=y
CONFIG_NET_SOCKETS=y
CONFIG_NET_NATIVE=n

CONFIG_HEAP_MEM_POOL_SIZE=4096
CONFIG_MAIN_STACK_SIZE=4096

CONFIG_MODEM_KEY_MGMT=y
CONFIG_LTE_LINK_CONTROL=y

CONFIG_LTE_NETWORK_MODE_LTE_M=n
CONFIG_LTE_NETWORK_MODE_NBIOT=y

CONFIG_LTE_AUTO_INIT_AND_CONNECT=y

Do you know how to solve this?

Thanks in advance.

[Håkon Alseth]

Hi,

 

Does your local carrier provide a DNS?

Could you try other examples, like mqtt_simple, to see if this works?

 

Remember to set "CONFIG_LTE_NETWORK_MODE_NBIOT=y" in prj.conf file before building.

 

Kind regards,

Håkon

[Saketaram]

I will.

For the record, when I previously used LTE LInk Monitor and set

AT+CFUN=4
AT%XSYSTEMMODE=0,1,1,0
AT+CFUN=1
AT+CFUN?

I got this screen.

Is this related to DNS?

[Saketaram]

Trying mqtt_simple.

I added the last 3 lines to prj.conf

#
# Copyright (c) 2019 Nordic Semiconductor ASA
#
# SPDX-License-Identifier: LicenseRef-BSD-5-Clause-Nordic
#

# Networking
CONFIG_NETWORKING=y
CONFIG_NET_NATIVE=n
CONFIG_NET_SOCKETS_OFFLOAD=y
CONFIG_NET_SOCKETS=y
CONFIG_NET_SOCKETS_POSIX_NAMES=y

# LTE link control
CONFIG_LTE_LINK_CONTROL=y
CONFIG_LTE_AUTO_INIT_AND_CONNECT=n

# BSD library
CONFIG_BSD_LIBRARY=y

# AT Host
CONFIG_UART_INTERRUPT_DRIVEN=y
CONFIG_AT_HOST_LIBRARY=y

# MQTT
CONFIG_MQTT_LIB=y
CONFIG_MQTT_LIB_TLS=n

# Appliaction
#CONFIG_MQTT_PUB_TOPIC="/my/publish/topic"
#CONFIG_MQTT_SUB_TOPIC="/my/subscribe/topic"
#CONFIG_MQTT_CLIENT_ID="my-client-id"
#CONFIG_MQTT_BROKER_HOSTNAME="mqtt.eclipse.org"
#CONFIG_MQTT_BROKER_PORT=1883

# Main thread
CONFIG_MAIN_STACK_SIZE=4096

CONFIG_HEAP_MEM_POOL_SIZE=2048

CONFIG_LTE_NETWORK_MODE_LTE_M=n
CONFIG_LTE_NETWORK_MODE_NBIOT=y

CONFIG_LTE_AUTO_INIT_AND_CONNECT=y

Then I compiled and flashed through command line.

And with PuTTY, I got this message:

*** Booting Zephyr OS build v2.1.99-ncs1  ***
+CEREG: 2,"0BF4","099E5765",9,0,0,"11100000","11100000"
+CEREG: 1,"0BF4","099E5765",9,,,"11100000","11100000"
The MQTT simple sample started
ERROR: getaddrinfo failed 22
ERROR: mqtt_connect -47

Does it clarify?

[Håkon Alseth]

Hi,

 

Thank you for the logs and testing this.

Unfortunately, this shows that your local carrier does not provide DNS.

 

When testing examples, you can manually resolve the hostname, for instance:

mqtt.eclipse.org resolves to "137.135.83.217" when I ping it at my end, then you can set this as the prj.conf::CONFIG_MQTT_BROKER_HOSTNAME="137.135.83.217"

 

Alternative can be to manually set the DNS, as a user has done in this post:

https://devzone.nordicsemi.com/f/nordic-q-a/50029/nrf9160-modem-firmware-v1-0-0-setting-custom-dns-server/235419#235419

 

Kind regards,

Håkon

[Saketaram]

Thanks. The telecom provider didn't enable DNS.