nRF9160 DK - Asset Tracker Application - Connect to EMEA nRF Cloud?

[Kevin Kotinkar]

Hi,

I am testing the nRF9160 DK and used the asset tracker application with the IBasis SIM.
Application works fine under CAT M1 network (IBasis SIM is roaming on o2/Telefonica in Germany), but I can't connect to the MQTT broker / nRF cloud on NB-IoT.
(Modem is attached on NB-IoT, signal level (RSRP, RSRQ) is good).

Most likely, this is due to latency issues, as MQTT runs on TCP, which already fairly heavy for NB IoT.

Secondly, I noticed that the application uses a NRF cloud / MQTT server in the US (east coast, Virgina).
Domain: a2n7tk1kp18wix-ats.iot.us-east-1.amazonaws.com

I can connect to MQTT brokers nearby in Europe on NB-IoT (used for example the MQTT sample application), TCP connection was stable enough to support MQTT.
Question is hence, is there a server/gateway for the nRF cloud MQTT broker in Europe or other regions than US East?

Thanks.

BR
Kevin

[Albrecht Markus Schellenberger]

Hello Kevin,

I’m not aware of any server/gateway for the nRF Cloud in Europe.

Would you mind sending me an application log that shows the failing connecting to the nRF Cloud on NB-IoT? I might wanna cross-check this with our nRF Cloud team.

Thanks and regards,

Markus

[Kevin Kotinkar]

Thank you, Markus.

Sure, I will do so soon, but in the next days.

BR
Kevin

[Kevin Kotinkar]

Hello Markus,

I am attaching two application logs, one taken in Berlin, the other one in Munich. Let me know if you see something interesting. For those 2 logs, I have used the pre-compiled asset tracker application, but I had same results when running my own compiled versions (haven't tested on NCS 1.6.0 though, only used NCS 1.5.0 with Zephyr 2.4.99.

(As said CAT-M works, let me know if a success log of that for cross comparison will be helpful).


Btw, to get DNS working on NB IoT I had to use legacy PCO mode with o2 / Telefonica in Germany (June 2021).

Best regards,
Kevin

Fullscreen nRF9160DK_asset_tracker_NBIOT_Berlin.log Download

[2021-06-25 11:13:11.885] *** Booting Zephyr OS build v2.4.99-ncs1  ***
[2021-06-25 11:13:11.885] I: Starting bootloader
[2021-06-25 11:13:11.885] I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
[2021-06-25 11:13:11.897] I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
[2021-06-25 11:13:11.905] I: Boot source: none
[2021-06-25 11:13:11.906] I: Swap type: none
[2021-06-25 11:13:12.182] I: Bootloader chainload address offset: 0x10000
[2021-06-25 11:13:12.188] I: Jumping to the first image slot*** Booting Zephyr OS build v2.4.99-ncs1  ***
[2021-06-25 11:13:12.194] Flash regions		Domain		Permissions
[2021-06-25 11:13:12.196] 00 02 0x00000 0x18000 	Secure		rwxl
[2021-06-25 11:13:12.196] 03 31 0x18000 0x100000 	Non-Secure	rwxl
[2021-06-25 11:13:12.196] 
[2021-06-25 11:13:12.204] Non-secure callable region 0 placed in flash region 2 with size 32.
[2021-06-25 11:13:12.205] 
[2021-06-25 11:13:12.378] SRAM region		Domain		Permissions
[2021-06-25 11:13:12.382] 00 07 0x00000 0x10000 	Secure		rwxl
[2021-06-25 11:13:12.387] 08 31 0x10000 0x40000 	Non-Secure	rwxl
[2021-06-25 11:13:12.387] 
[2021-06-25 11:13:12.387] Peripheral		Domain		Status
[2021-06-25 11:13:12.387] 00 NRF_P0               Non-Secure	OK
[2021-06-25 11:13:12.395] 01 NRF_CLOCK            Non-Secure	OK
[2021-06-25 11:13:12.396] 02 NRF_RTC0             Non-Secure	OK
[2021-06-25 11:13:12.396] 03 NRF_RTC1             Non-Secure	OK
[2021-06-25 11:13:12.405] 04 NRF_NVMC             Non-Secure	OK
[2021-06-25 11:13:12.406] 05 NRF_UARTE1           Non-Secure	OK
[2021-06-25 11:13:12.406] 06 NRF_UARTE2           Secure		SKIP
[2021-06-25 11:13:12.416] 07 NRF_TWIM2            Non-Secure	OK
[2021-06-25 11:13:12.416] 08 NRF_SPIM3            Non-Secure	OK
[2021-06-25 11:13:12.416] 09 NRF_TIMER0           Non-Secure	OK
[2021-06-25 11:13:12.425] 10 NRF_TIMER1           Non-Secure	OK
[2021-06-25 11:13:12.425] 11 NRF_TIMER2           Non-Secure	OK
[2021-06-25 11:13:12.425] 12 NRF_SAADC            Non-Secure	OK
[2021-06-25 11:13:12.436] 13 NRF_PWM0             Non-Secure	OK
[2021-06-25 11:13:12.436] 14 NRF_PWM1             Non-Secure	OK
[2021-06-25 11:13:12.436] 15 NRF_PWM2             Non-Secure	OK
[2021-06-25 11:13:12.446] 16 NRF_PWM3             Non-Secure	OK
[2021-06-25 11:13:12.446] 17 NRF_WDT              Non-Secure	OK
[2021-06-25 11:13:12.446] 18 NRF_IPC              Non-Secure	OK
[2021-06-25 11:13:12.456] 19 NRF_VMC              Non-Secure	OK
[2021-06-25 11:13:12.458] 20 NRF_FPU              Non-Secure	OK
[2021-06-25 11:13:12.458] 21 NRF_EGU1             Non-Secure	OK
[2021-06-25 11:13:12.465] 22 NRF_EGU2             Non-Secure	OK
[2021-06-25 11:13:12.465] 23 NRF_DPPIC            Non-Secure	OK
[2021-06-25 11:13:12.465] 24 NRF_REGULATORS       Non-Secure	OK
[2021-06-25 11:13:12.476] 25 NRF_GPIOTE1          Non-Secure	OK
[2021-06-25 11:13:12.476] 
[2021-06-25 11:13:12.476] SPM: NS image at 0x1c200
[2021-06-25 11:13:12.482] SPM: NS MSP at 0x20025598
[2021-06-25 11:13:12.486] SPM: NS reset vector at 0x26805
[2021-06-25 11:13:12.486] SPM: prepare to jump to Non-Secure image.
[2021-06-25 11:13:12.697] *** Booting Zephyr OS build v2.4.99-ncs1  ***
[2021-06-25 11:13:12.697] [00:00:00.206,237] <inf> asset_tracker: Asset tracker started
[2021-06-25 11:13:12.706] [00:00:00.212,432] <inf> watchdog: Watchdog timeout installed. Timeout: 60000
[2021-06-25 11:13:12.715] [00:00:00.220,031] <inf> watchdog: Watchdog started
[2021-06-25 11:13:12.715] [00:00:00.225,402] <inf> watchdog: Watchdog feed enabled. Timeout: 30000
[2021-06-25 11:13:12.726] [00:00:00.233,276] <dbg> nrf_cloud_transport.nct_settings_set: Settings key: p_sesh, size: 4
[2021-06-25 11:13:12.736] [00:00:00.242,187] <dbg> nrf_cloud_transport.nct_settings_set: Read setting val: 1
[2021-06-25 11:13:12.755] [00:00:00.257,385] <dbg> nrf_cloud_transport.nct_client_id_get: client_id = nrf-352656106651436
[2021-06-25 11:13:12.764] [00:00:00.266,601] <dbg> nrf_cloud_transport.nct_topics_populate: shadow_base_topic: $aws/things/nrf-352656106651436/shadow
[2021-06-25 11:13:12.776] [00:00:00.278,350] <dbg> nrf_cloud_transport.nct_topics_populate: accepted_topic: nrf-352656106651436/shadow/get/accepted
[2021-06-25 11:13:12.785] [00:00:00.289,947] <dbg> nrf_cloud_transport.nct_topics_populate: rejected_topic: $aws/things/nrf-352656106651436/shadow/get/rejected
[2021-06-25 11:13:12.796] [00:00:00.302,490] <dbg> nrf_cloud_transport.nct_topics_populate: update_delta_topic: $aws/things/nrf-352656106651436/shadow/update/delta
[2021-06-25 11:13:12.806] [00:00:00.315,551] <dbg> nrf_cloud_transport.nct_topics_populate: update_topic: $aws/things/nrf-352656106651436/shadow/update
[2021-06-25 11:13:12.825] [00:00:00.327,484] <dbg> nrf_cloud_transport.nct_topics_populate: shadow_get_topic: $aws/things/nrf-352656106651436/shadow/get
[2021-06-25 11:13:12.836] [00:00:00.339,538] <inf> asset_tracker: Connecting to LTE network.
[2021-06-25 11:13:12.842] [00:00:00.346,252] <inf> asset_tracker: This may take several minutes.
[2021-06-25 11:13:12.864] [00:00:00.367,645] <inf> lte_lc: Using legacy LTE PCO mode...
[2021-06-25 11:13:15.515] +CEREG: 2,"0899","00535665",9
[2021-06-25 11:13:15.515] [00:00:03.022,033] <inf> asset_tracker: LTE cell changed: Cell ID: 5461605, Tracking area: 2201
[2021-06-25 11:13:16.515] +CSCON: 1
[2021-06-25 11:13:16.515] [00:00:04.023,590] <inf> asset_tracker: RRC mode: Connected
[2021-06-25 11:13:24.477] +CEREG: 5,"0899","00535665",9,,,"11100000","00101100"
[2021-06-25 11:13:24.477] [00:00:11.985,931] <inf> asset_tracker: Connected to LTE network.
[2021-06-25 11:13:24.485] [00:00:11.992,675] <inf> asset_tracker: Connecting to cloud, attempt 1 of 8
[2021-06-25 11:13:24.496] [00:00:12.000,122] <inf> asset_tracker: Cloud connection request sent.
[2021-06-25 11:13:24.496] [00:00:12.007,110] <inf> asset_tracker: Connection response timeout is set to 30 seconds.
[2021-06-25 11:13:24.506] [00:00:12.015,960] <inf> asset_tracker: Network registration status: Connected - roaming
[2021-06-25 11:13:24.516] [00:00:12.024,505] <inf> asset_tracker: PSM parameter update: TAU: 43200, Active time: -1
[2021-06-25 11:13:24.525] [00:00:12.033,325] <dbg> nrf_cloud.api_event_handler: NRF_CLOUD_EVT_TRANSPORT_CONNECTING
[2021-06-25 11:13:24.536] [00:00:12.041,931] <inf> asset_tracker: CLOUD_EVT_CONNECTING
[2021-06-25 11:13:27.047] at+cereg?+CEREG: 5,5,"0899","00535665",9,,,"11100000","00101100"
[2021-06-25 11:13:28.475] OK
[2021-06-25 11:13:28.895] at+ces[00:00:17.641,601] <dbg> nrf_cloud_transport.nct_connect: IPv4 address: 34.206.75.181
[2021-06-25 11:13:30.145] [00:00:17.649,932] <dbg> nrf_cloud_transport.nct_mqtt_connect: MQTT clean session flag: 0
[2021-06-25 11:13:30.159] q+CESQ: 99,99,255,255,20,44
[2021-06-25 11:13:30.356] OK
[2021-06-25 11:13:31.167] [00:00:18.674,713] <inf> asset_tracker: DATE_TIME_OBTAINED_NTP
[2021-06-25 11:13:36.577] at+cgpaddr+CGPADDR: 0,"10.160.40.236"
[2021-06-25 11:13:38.046] OK
[2021-06-25 11:13:45.156] at%xmonitor%XMONITOR: 5,"","","26203","0899",9,20,"00535665",366,6190,44,38,"","11100000","00101100","01011110"
[2021-06-25 11:13:47.056] OK
[2021-06-25 11:14:50.928] [00:01:38.434,234] <dbg> nrf_cloud_transport.nct_mqtt_connect: mqtt_connect failed -104
[2021-06-25 11:14:50.929] [00:01:38.442,749] <err> nrf_cloud: nRF cloud connect failed -104
[2021-06-25 11:14:50.938] [00:01:38.449,645] <dbg> nrf_cloud.api_event_handler: NRF_CLOUD_EVT_TRANSPORT_CONNECTING
[2021-06-25 11:14:50.948] [00:01:38.458,343] <err> nrf_cloud: nRF cloud connect failed -5
[2021-06-25 11:14:50.958] [00:01:38.465,087] <inf> asset_tracker: CLOUD_EVT_CONNECTING
[2021-06-25 11:14:50.960] [00:01:38.471,221] <err> asset_tracker: Failed to connect to cloud, error -5
[2021-06-25 11:14:50.968] [00:01:38.479,125] <err> asset_tracker: Device will reboot in 300 seconds
[2021-06-25 11:14:50.978] [00:01:38.486,755] <err> asset_tracker: LTE link disconnect
[2021-06-25 11:14:51.430] +CEREG: 0
[2021-06-25 11:14:51.435] [00:01:38.942,047] <inf> asset_tracker: LTE cell changed: Cell ID: -1, Tracking area: -1
[2021-06-25 11:14:52.263] +CSCON: 0
[2021-06-25 11:14:52.263] [00:01:39.770,416] <inf> asset_tracker: RRC mode: Idle
[2021-06-25 11:14:52.478] [00:01:39.984,466] <err> asset_tracker: Shutdown modem

Fullscreen nRF9160DK_asset_tracker_NBIOT_Munich.log Download

[2021-06-23 10:20:05.880] *** Booting Zephyr OS build v2.4.99-ncs1  ***
[2021-06-23 10:20:05.880] I: Starting bootloader
[2021-06-23 10:20:05.880] I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
[2021-06-23 10:20:05.880] I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
[2021-06-23 10:20:05.896] I: Boot source: none
[2021-06-23 10:20:05.896] I: Swap type: none
[2021-06-23 10:20:06.166] I: Bootloader chainload address offset: 0x10000
[2021-06-23 10:20:06.166] I: Jumping to the first image slot*** Booting Zephyr OS build v2.4.99-ncs1  ***
[2021-06-23 10:20:06.182] Flash regions		Domain		Permissions
[2021-06-23 10:20:06.182] 00 02 0x00000 0x18000 	Secure		rwxl
[2021-06-23 10:20:06.182] 03 31 0x18000 0x100000 	Non-Secure	rwxl
[2021-06-23 10:20:06.182] 
[2021-06-23 10:20:06.182] Non-secure callable region 0 placed in flash region 2 with size 32.
[2021-06-23 10:20:06.197] 
[2021-06-23 10:20:06.366] SRAM region		Domain		Permissions
[2021-06-23 10:20:06.366] 00 07 0x00000 0x10000 	Secure		rwxl
[2021-06-23 10:20:06.366] 08 31 0x10000 0x40000 	Non-Secure	rwxl
[2021-06-23 10:20:06.382] 
[2021-06-23 10:20:06.382] Peripheral		Domain		Status
[2021-06-23 10:20:06.382] 00 NRF_P0               Non-Secure	OK
[2021-06-23 10:20:06.382] 01 NRF_CLOCK            Non-Secure	OK
[2021-06-23 10:20:06.382] 02 NRF_RTC0             Non-Secure	OK
[2021-06-23 10:20:06.382] 03 NRF_RTC1             Non-Secure	OK
[2021-06-23 10:20:06.398] 04 NRF_NVMC             Non-Secure	OK
[2021-06-23 10:20:06.398] 05 NRF_UARTE1           Non-Secure	OK
[2021-06-23 10:20:06.398] 06 NRF_UARTE2           Secure		SKIP
[2021-06-23 10:20:06.398] 07 NRF_TWIM2            Non-Secure	OK
[2021-06-23 10:20:06.398] 08 NRF_SPIM3            Non-Secure	OK
[2021-06-23 10:20:06.413] 09 NRF_TIMER0           Non-Secure	OK
[2021-06-23 10:20:06.413] 10 NRF_TIMER1           Non-Secure	OK
[2021-06-23 10:20:06.420] 11 NRF_TIMER2           Non-Secure	OK
[2021-06-23 10:20:06.420] 12 NRF_SAADC            Non-Secure	OK
[2021-06-23 10:20:06.420] 13 NRF_PWM0             Non-Secure	OK
[2021-06-23 10:20:06.420] 14 NRF_PWM1             Non-Secure	OK
[2021-06-23 10:20:06.435] 15 NRF_PWM2             Non-Secure	OK
[2021-06-23 10:20:06.435] 16 NRF_PWM3             Non-Secure	OK
[2021-06-23 10:20:06.435] 17 NRF_WDT              Non-Secure	OK
[2021-06-23 10:20:06.435] 18 NRF_IPC              Non-Secure	OK
[2021-06-23 10:20:06.435] 19 NRF_VMC              Non-Secure	OK
[2021-06-23 10:20:06.451] 20 NRF_FPU              Non-Secure	OK
[2021-06-23 10:20:06.451] 21 NRF_EGU1             Non-Secure	OK
[2021-06-23 10:20:06.451] 22 NRF_EGU2             Non-Secure	OK
[2021-06-23 10:20:06.451] 23 NRF_DPPIC            Non-Secure	OK
[2021-06-23 10:20:06.467] 24 NRF_REGULATORS       Non-Secure	OK
[2021-06-23 10:20:06.467] 25 NRF_GPIOTE1          Non-Secure	OK
[2021-06-23 10:20:06.467] 
[2021-06-23 10:20:06.467] SPM: NS image at 0x1c200
[2021-06-23 10:20:06.467] SPM: NS MSP at 0x200255a0
[2021-06-23 10:20:06.467] SPM: NS reset vector at 0x267d5
[2021-06-23 10:20:06.467] SPM: prepare to jump to Non-Secure image.
[2021-06-23 10:20:06.683] *** Booting Zephyr OS build v2.4.99-ncs1  ***
[2021-06-23 10:20:06.683] [00:00:00.206,207] <inf> asset_tracker: Asset tracker started
[2021-06-23 10:20:06.699] [00:00:00.212,402] <inf> watchdog: Watchdog timeout installed. Timeout: 60000
[2021-06-23 10:20:06.699] [00:00:00.220,001] <inf> watchdog: Watchdog started
[2021-06-23 10:20:06.714] [00:00:00.225,372] <inf> watchdog: Watchdog feed enabled. Timeout: 30000
[2021-06-23 10:20:06.721] [00:00:00.233,825] <dbg> nrf_cloud_transport.nct_settings_set: Settings key: p_sesh, size: 4
[2021-06-23 10:20:06.721] [00:00:00.242,736] <dbg> nrf_cloud_transport.nct_settings_set: Read setting val: 1
[2021-06-23 10:20:06.737] [00:00:00.258,300] <dbg> nrf_cloud_transport.nct_client_id_get: client_id = nrf-352656106651436
[2021-06-23 10:20:06.752] [00:00:00.267,547] <dbg> nrf_cloud_transport.nct_topics_populate: shadow_base_topic: $aws/things/nrf-352656106651436/shadow
[2021-06-23 10:20:06.768] [00:00:00.279,327] <dbg> nrf_cloud_transport.nct_topics_populate: accepted_topic: nrf-352656106651436/shadow/get/accepted
[2021-06-23 10:20:06.768] [00:00:00.290,924] <dbg> nrf_cloud_transport.nct_topics_populate: rejected_topic: $aws/things/nrf-352656106651436/shadow/get/rejected
[2021-06-23 10:20:06.783] [00:00:00.303,649] <dbg> nrf_cloud_transport.nct_topics_populate: update_delta_topic: $aws/things/nrf-352656106651436/shadow/update/delta
[2021-06-23 10:20:06.799] [00:00:00.316,619] <dbg> nrf_cloud_transport.nct_topics_populate: update_topic: $aws/things/nrf-352656106651436/shadow/update
[2021-06-23 10:20:06.815] [00:00:00.328,552] <dbg> nrf_cloud_transport.nct_topics_populate: shadow_get_topic: $aws/things/nrf-352656106651436/shadow/get
[2021-06-23 10:20:06.821] [00:00:00.340,606] <inf> asset_tracker: Connecting to LTE network.
[2021-06-23 10:20:06.836] [00:00:00.347,320] <inf> asset_tracker: This may take several minutes.
[2021-06-23 10:20:06.852] [00:00:00.370,758] <inf> lte_lc: Using legacy LTE PCO mode...
[2021-06-23 10:20:11.392] +CEREG: 2,"1421","01871065",9
[2021-06-23 10:20:11.392] [00:00:04.911,193] <inf> asset_tracker: LTE cell changed: Cell ID: 25628773, Tracking area: 5153
[2021-06-23 10:20:22.289] +CSCON: 1
[2021-06-23 10:20:22.292] [00:00:15.799,468] <inf> asset_tracker: RRC mode: Connected
[2021-06-23 10:20:46.274] +CEREG: 5,"1421","01871065",9,,,"11100000","00101100"
[2021-06-23 10:20:46.274] [00:00:39.789,459] <inf> asset_tracker: Connected to LTE network.
[2021-06-23 10:20:46.274] [00:00:39.796,142] <inf> asset_tracker: Connecting to cloud, attempt 1 of 8
[2021-06-23 10:20:46.289] [00:00:39.803,619] <inf> asset_tracker: Cloud connection request sent.
[2021-06-23 10:20:46.289] [00:00:39.810,607] <inf> asset_tracker: Connection response timeout is set to 30 seconds.
[2021-06-23 10:20:46.305] [00:00:39.819,458] <inf> asset_tracker: Network registration status: Connected - roaming
[2021-06-23 10:20:46.305] [00:00:39.828,002] <inf> asset_tracker: PSM parameter update: TAU: 43200, Active time: -1
[2021-06-23 10:20:46.321] [00:00:39.836,791] <dbg> nrf_cloud.api_event_handler: NRF_CLOUD_EVT_TRANSPORT_CONNECTING
[2021-06-23 10:20:46.321] [00:00:39.845,397] <inf> asset_tracker: CLOUD_EVT_CONNECTING
[2021-06-23 10:21:07.149] [00:01:00.672,912] <wrn> date_time: sntp_query, error: -116
[2021-06-23 10:21:16.756] at+cereg?+CEREG: 5,5,"1421","01871065",9,,,"11100000","00101100"
[2021-06-23 10:21:18.871] OK
[2021-06-23 10:21:19.816] at+cgpaddr+CGPADDR: 0,"10.160.177.12"
[2021-06-23 10:21:21.600] OK
[2021-06-23 10:21:23.291] at+cgdcont?+CGDCONT: 0,"IP","IBASIS.IOT","10.160.177.12",0,0
[2021-06-23 10:21:25.117] OK
[2021-06-23 10:21:25.446] at+cgatt?+CGATT: 1
[2021-06-23 10:21:27.248] OK
[2021-06-23 10:21:32.936] at+cesq+CESQ: 99,99,255,255,25,57
[2021-06-23 10:21:34.527] OK
[2021-06-23 10:21:51.611] at%xmonitor%XMONITOR: 5,"","","26203","1421",9,20,"01871065",21,6152,59,40,"","11100000","00101100","01011110"
[2021-06-23 10:21:54.299] OK
[2021-06-23 10:22:12.153] [00:02:05.678,924] <dbg> nrf_cloud_transport.nct_connect: getaddrinfo failed -11
[2021-06-23 10:22:12.168] [00:02:05.686,920] <dbg> nrf_cloud.api_event_handler: NRF_CLOUD_EVT_TRANSPORT_CONNECTING
[2021-06-23 10:22:12.168] [00:02:05.695,556] <inf> asset_tracker: CLOUD_EVT_CONNECTING
[2021-06-23 10:22:12.184] [00:02:05.701,812] <err> asset_tracker: Failed to connect to cloud, error -3
[2021-06-23 10:22:12.184] [00:02:05.709,625] <err> asset_tracker: Network error, check cloud configuration
[2021-06-23 10:22:34.729] at+credesq+CESQ: 99,99,255,255,24,58
[2021-06-23 10:22:37.842] OK
[2021-06-23 10:23:22.171] [00:03:15.689,239] <wrn> date_time: getaddrinfo, error: -11
[2021-06-23 10:23:38.044] AT%XEPCO?%XEPCO: 0
[2021-06-23 10:23:41.471] OK
[2021-06-23 10:24:32.187] [00:04:25.707,061] <wrn> date_time: getaddrinfo, error: -11
[2021-06-23 10:25:42.192] [00:05:35.724,822] <wrn> date_time: getaddrinfo, error: -11
[2021-06-23 10:25:55.739] atOK
[2021-06-23 10:25:58.951] at+cresq+CESQ: 99,99,255,255,24,62
[2021-06-23 10:26:01.837] OK
[2021-06-23 10:26:04.855] at%xmonitor%XMONITOR: 5,"","","26203","1421",9,20,"01871065",21,6152,62,41,"","11100000","00101100","01011110"
[2021-06-23 10:26:08.612] OK
[2021-06-23 10:26:09.244] at+cops?+COPS: 0,2,"26203",9
[2021-06-23 10:26:10.613] OK
[2021-06-23 10:26:11.398] at+cereg?+CEREG: 5,5,"1421","01871065",9,,,"11100000","00101100"
[2021-06-23 10:26:12.849] OK

).

[Albrecht Markus Schellenberger]

Hello Kevin,

Thanks a lot for the logs! The device in Berlin reports a connection reset error, while the device in Munich claims that the host could not be found with the available network interfaces (which might be the same root cause, only in different words).

Considering the national iBasis coverage of NB-IoT in Germany, I’m not really sure how much support we can provide here.

But I’ll check this with our nRF Cloud team and see if they have any solution to your problem.

Regards,

Markus

[Kevin Kotinkar]

Hi Markus,

thank you for the error code explanations. 

I have to admit that I also had the DK connected to the cloud on NB-IoT once (out of 15 tries maybe). I had my DK running outdoors. However, the XMONITOR and CESQ AT commands usually report fairly good cellular signal parameters, also indoors, thus I thought the cellular coverage is actually not too bad and not the root cause of the issue.

I don't know if there are any tiimeouts for the MQTT connection / cloud connection that I could increase just to see if it works most consistently. Could be the backend of the MNO/MVNO that causes the delays here, resulting in connection issues on TCP, MQTT or another higher layer.

Regarding the actual coverage and as I mentioned previously, iBasis seems to only/or mainly roam on Telefonica/o2 Germany. For those interested, this is the best / latest coverage map of Telefonica Germany that I found:
https://www.o2online.de/netz/


Please let me know if you find out anything further, otherwise feel free to close the case.

BR
Kevin