Network issues with ESP8266 shield connected to nRF9160

Question

I am trying to use an ESP8266 ( ESP-01) to add Wifi capabilities to a nRF9160 project board. I am using nRF Connect SDK V2.9.0 and the V2.9.0 Toolchain. To set it up I followed the basic directions here: https://docs.zephyrproject.org/latest/boards/shields/esp_8266/doc/index.html I wanted to test it using the standard wifi shell sample. I took the In the CMakeList.txt file I added the following line: set(SHIELD esp_8266) And I created an overlay file containing the mapping to the Tx/Rx pins to communicate with it: &uart1 { status = "okay"; current-speed = <115200>; pinctrl-0 = <&uart1_default>; pinctrl-1 = <&uart1_sleep>; pinctrl-names = "default", "default"; esp8266 { compatible = "espressif,esp-at"; label = "esp8266"; status = "okay"; }; }; Since I wanted to test DNS and some other more advanced features I added the following lines to the prj.conf file: CONFIG_DNS_RESOLVER=y CONFIG_NET_TCP=y CONFIG_WIFI_LOG_LEVEL_ERR=y CONFIG_NET_L2_WIFI_SHELL=y CONFIG_DNS_SERVER_IP_ADDRESSES =y CONFIG_DNS_SERVER1 = "8.8.8.8" Having done all of that I compiled and uploaded the firmware and tested it out. I am able to scan the wifi and connect: wifi scan Scan requested Num | SSID (len) | Chan (Band) | RSSI | Security | BSSID | MFP 1 | Tattler 7 | 1 (2.4GHz) | -77 | WPA2-PSK | | Disable 2 | 0 | 1 (2.4GHz) | -76 | WPA2-PSK | | Disable 3 | eigenair 8 | 9 (2.4GHz) | -69 | WPA2-PSK | | Disable 4 | I-Guest 9 | 6 (2.4GHz) | -72 | OPEN | | Disable 5 | I_Partners 12 | 6 (2.4GHz) | -71 | WPA2-PSK | | Disable 6 | R_Visitor 12 | 6 (2.4GHz) | -80 | OPEN | | Disable 7 | txrx2.4 7 | 9 (2.4GHz) | -59 | WPA2-PSK | | Disable Scan request done uart:~$ wifi connect -s "WL-001" -p 123456 -k 1 Connection requested Connected ---- Sent utf8 encoded message: "wifi status " ---- wifi status Status: successful ================== State: COMPLETED Interface Mode: STATION Link Mode: UNKNOWN SSID: txrx2.4 BSSID: D8:47:32:74:F3:E6 Band: 2.4GHz Channel: 9 Security: UNKNOWN MFP: UNKNOWN RSSI: -60 Beacon Interval: 0 DTIM: 0 TWT: Not supported Current PHY TX rate (Mbps) : 0 And I have confirmed it has been assigned an IP address and has at least one : net iface Interface wlan0 (0x20000560) (IP Offload) [1] ===================================== Link addr : 50:02:91:51:74:8F MTU : 2048 Flags : AUTO_START,IPv4 Device : esp8266 (0x27324) Status : oper=UP, admin=UP, carrier=ON IPv4 unicast addresses (max 1): 10.10.51.28/255.255.254.0 DHCP preferred infinite IPv4 multicast addresses (max 2): 224.0.0.1 IPv4 gateway : 10.10.50.1 DHCPv4 lease time : 0 DHCPv4 renew time : 0 DHCPv4 server : 0.0.0.0 DHCPv4 requested : 0.0.0.0 DHCPv4 state : disabled DHCPv4 attempts : 0 net dns DNS servers: 8.8.8.8:53 Pending queries: However when I then try to use other commands like ping or dns they always fail: --- Sent utf8 encoded message: "net ping 10.10.50.205 " ---- net ping 10.10.50.205 PING 10.10.50.205 Failed to send ping,uart:~$ ---- Sent utf8 encoded message: "net dns google.com " ---- net dns google.com Cannot resolve 'google.com' (-22) I have searched through all of the other problem tickets and although I found a couple related to the ESP8266 and Wifi add-on shields in general they seem to be precursors to getting to this state (i.e. they can't talk to the card at all or it crashes). I cannot find anything related to this issue or even close to it. I'm fairly certain this is a Nordic-specific issue (somehow) because if I do this same process connected to an ESP32-based board it works. However the Devkit versions are different: nRF Connect SDK V2.9.0 vs. Zephyr v4.1.0-rc2. Thoughts or suggestions? I've gone through