EG800K NEtworkManager does not detect USB Modem

Julio.Cerveza · August 3, 2026, 6:41pm

Hello,

wanted to know if anyone encountered any limitations in respect to EG800K-EU Modem and Raspberry 5 “Raspbian GNU/Linux 13 (trixie)”.

I cant register my usb interface, my LTE Modem is connected through usb, within NetworkManager…

I can ping an ip directly, but as not registered within nm I am missing DNS as well…

My firmware version is: EG800KEULCR07A07M04

Cheers

jfrog · August 3, 2026, 7:55pm

Show the output of cat /sys/kernel/debug/usb/devices

Julio.Cerveza · August 4, 2026, 6:44pm

ok, here some more infos,

user@chupi:~ $ mmcli -L

    /org/freedesktop/ModemManager1/Modem/1 [Quectel] EG800K



user@chupi:~ $ systemctl status NetworkManager

● NetworkManager.service - Network Manager

     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; preset: enabled)

     Active: active (running) since Mon 2026-08-03 21:40:36 CEST; 7min ago

 Invocation: b3713c24358845bdba251a6fc4323b8b

       Docs: man:NetworkManager(8)

   Main PID: 921 (NetworkManager)

      Tasks: 4 (limit: 4915)

        CPU: 527ms

     CGroup: /system.slice/NetworkManager.service

             └─921 /usr/sbin/NetworkManager --no-daemon


Aug 03 21:42:26 chupi NetworkManager[921]: <info>  [1785786146.9431] manager: NetworkManager state is now CONNECTED_GLOBAL

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6346] device (usb0): state change: activated -> unmanaged (reason 'unmanaged-link-not-init', managed-typ>

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6735] dhcp4 (usb0): canceled DHCP transaction

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6736] dhcp4 (usb0): activation: beginning transaction (timeout in 45 seconds)

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6736] dhcp4 (usb0): state changed no lease

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6741] manager: NetworkManager state is now DISCONNECTED

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6890] manager: (ttyUSB2): new Broadband device (/org/freedesktop/NetworkManager/Devices/7)

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6893] device (ttyUSB2): state change: unmanaged -> unavailable (reason 'managed', managed-type: 'externa>

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.6896] device (ttyUSB2): modem state 'enabling'

Aug 03 21:42:31 chupi NetworkManager[921]: <info>  [1785786151.7458] device (ttyUSB2): state change: unavailable -> disconnected (reason 'none', managed-type: 'full')

lines 1-21/21 (END)




user@chupi:~ $ cat /sys/kernel/debug/usb/devices 


T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 2

B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0

D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1

P:  Vendor=1d6b ProdID=0002 Rev= 6.12

S:  Manufacturer=Linux 6.12.47+rpt-rpi-v8 xhci-hcd

S:  Product=xHCI Host Controller

S:  SerialNumber=xhci-hcd.0

C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA

I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub

E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms


T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  2 Spd=12   MxCh= 0

D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=32 #Cfgs=  1

P:  Vendor=413c ProdID=2514 Rev= 2.22

S:  Manufacturer=Dell Computer Corp

S:  Product=Dell Universal Receiver

C:* #Ifs= 3 Cfg#= 1 Atr=a0 MxPwr=100mA

I:* If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=01 Prot=01 Driver=usbhid

E:  Ad=81(I) Atr=03(Int.) MxPS=   8 Ivl=4ms

I:* If#= 1 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=01 Prot=02 Driver=usbhid

E:  Ad=82(I) Atr=03(Int.) MxPS=   8 Ivl=2ms

I:* If#= 2 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=00 Driver=usbhid

E:  Ad=83(I) Atr=03(Int.) MxPS=  32 Ivl=2ms


T:  Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=5000 MxCh= 1

B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0

D:  Ver= 3.00 Cls=09(hub  ) Sub=00 Prot=03 MxPS= 9 #Cfgs=  1

P:  Vendor=1d6b ProdID=0003 Rev= 6.12

S:  Manufacturer=Linux 6.12.47+rpt-rpi-v8 xhci-hcd

S:  Product=xHCI Host Controller

S:  SerialNumber=xhci-hcd.0

C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA

I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub

E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms


T:  Bus=03 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 2

B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0

D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1

P:  Vendor=1d6b ProdID=0002 Rev= 6.12

S:  Manufacturer=Linux 6.12.47+rpt-rpi-v8 xhci-hcd

S:  Product=xHCI Host Controller

S:  SerialNumber=xhci-hcd.1

C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA

I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub

E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms


T:  Bus=03 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  5 Spd=480  MxCh= 0

D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1

P:  Vendor=2c7c ProdID=6002 Rev= 3.18

S:  Manufacturer=Quectel

S:  Product=EG800K-EU

S:  SerialNumber=0000

C:* #Ifs= 5 Cfg#= 1 Atr=e0 MxPwr=500mA

A:  FirstIf#= 0 IfCount= 2 Cls=02(comm.) Sub=06 Prot=00

I:* If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=cdc_ether

E:  Ad=87(I) Atr=03(Int.) MxPS=  64 Ivl=4096ms

I:  If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether

I:* If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether

E:  Ad=83(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms

E:  Ad=0c(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

I:* If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=00 Prot=00 Driver=option

E:  Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms

E:  Ad=0b(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option

E:  Ad=89(I) Atr=03(Int.) MxPS=  64 Ivl=4096ms

E:  Ad=86(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms

E:  Ad=0f(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option

E:  Ad=88(I) Atr=03(Int.) MxPS=  64 Ivl=4096ms

E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms

E:  Ad=0a(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms


T:  Bus=04 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=5000 MxCh= 1

B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0

D:  Ver= 3.00 Cls=09(hub  ) Sub=00 Prot=03 MxPS= 9 #Cfgs=  1

P:  Vendor=1d6b ProdID=0003 Rev= 6.12

S:  Manufacturer=Linux 6.12.47+rpt-rpi-v8 xhci-hcd

S:  Product=xHCI Host Controller

S:  SerialNumber=xhci-hcd.1

C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA

I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub

E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

jfrog · August 4, 2026, 7:00pm

Get rid of ModemManager completely and setup a regular DHCP interface.

Julio.Cerveza · August 5, 2026, 5:41pm

are you talking about sudo dhclient usb0 ? (usb0 is my LTE interface)

jfrog · August 5, 2026, 5:49pm

Please refer to your Linux distro documentation.

Julio.Cerveza · August 5, 2026, 6:33pm

ok, what I did,

Open the terminal via SSH or direct desktop access.
Type sudo nmtui to launch the NetworkManager text interface.
Select Edit a connection.
Choose your interface USB-LTE
Go to IPv4 CONFIGURATION, change it from Manual to Automatic → was already automatic
Clear out any manual entries → no entries were present
Restart Pi

unfortunatelly I still have issue with the connection, I am loosing ping after short time and I am not able to retrigger ping again… ModemManager is offline.

AT+QCFG="usbnet"
+QCFG: "usbnet",1

AT+QNETDEVCTL?
+QNETDEVCTL: 3,1,1,1

AT+QNETDEVCTL=3,1
OK

AT+QNETDEVCTL?
+QNETDEVCTL: 3,1,0,1


user@chupi:~ $ systemctl status NetworkManager
● NetworkManager.service - Network Manager
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; preset: enabled)
     Active: active (running) since Wed 2026-08-05 20:09:37 CEST; 6min ago
 Invocation: b3195f7be93546eaa5d200014e5a9b9d
       Docs: man:NetworkManager(8)
   Main PID: 954 (NetworkManager)
      Tasks: 4 (limit: 4915)
        CPU: 490ms
     CGroup: /system.slice/NetworkManager.service
             └─954 /usr/sbin/NetworkManager --no-daemon

Aug 05 20:09:41 chupi NetworkManager[954]: <info>  [1785953381.8348] dhcp6 (wlan0): state changed new lease, address=2a02:8070:2482:81c0::9df5
Aug 05 20:09:42 chupi NetworkManager[954]: <info>  [1785953382.4349] device (usb0): carrier: link connected
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.0721] dhcp4 (usb0): state changed new lease, address=192.168.43.100, acd pending
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.2397] dhcp4 (usb0): state changed new lease, address=192.168.43.100
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.2406] policy: set 'LTE-USB' (usb0) as default for IPv4 routing and DNS
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.2622] device (usb0): state change: ip-config -> ip-check (reason 'none', managed-type: 'full')
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3006] device (usb0): state change: ip-check -> secondaries (reason 'none', managed-type: 'full')
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3012] device (usb0): state change: secondaries -> activated (reason 'none', managed-type: 'full')
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3017] device (usb0): Activation: successful, device activated.
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3021] manager: startup complete
user@chupi:~ $ ip route
default via 192.168.43.1 dev usb0 proto dhcp src 192.168.43.100 metric 100 
default via 192.168.0.1 dev wlan0 proto static metric 600 
192.168.0.0/24 dev wlan0 proto kernel scope link src 192.168.0.245 metric 600 
192.168.43.0/24 dev usb0 proto kernel scope link src 192.168.43.100 metric 100 
user@chupi:~ $ ip route
default via 192.168.43.1 dev usb0 proto dhcp src 192.168.43.100 metric 100 
default via 192.168.0.1 dev wlan0 proto static metric 600 
192.168.0.0/24 dev wlan0 proto kernel scope link src 192.168.0.245 metric 600 
192.168.43.0/24 dev usb0 proto kernel scope link src 192.168.43.100 metric 100 
user@chupi:~ $ systemctl status NetworkManager
● NetworkManager.service - Network Manager
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; preset: enabled)
     Active: active (running) since Wed 2026-08-05 20:09:37 CEST; 7min ago
 Invocation: b3195f7be93546eaa5d200014e5a9b9d
       Docs: man:NetworkManager(8)
   Main PID: 954 (NetworkManager)
      Tasks: 4 (limit: 4915)
        CPU: 507ms
     CGroup: /system.slice/NetworkManager.service
             └─954 /usr/sbin/NetworkManager --no-daemon

Aug 05 20:09:41 chupi NetworkManager[954]: <info>  [1785953381.8348] dhcp6 (wlan0): state changed new lease, address=2a02:8070:2482:81c0::9df5
Aug 05 20:09:42 chupi NetworkManager[954]: <info>  [1785953382.4349] device (usb0): carrier: link connected
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.0721] dhcp4 (usb0): state changed new lease, address=192.168.43.100, acd pending
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.2397] dhcp4 (usb0): state changed new lease, address=192.168.43.100
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.2406] policy: set 'LTE-USB' (usb0) as default for IPv4 routing and DNS
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.2622] device (usb0): state change: ip-config -> ip-check (reason 'none', managed-type: 'full')
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3006] device (usb0): state change: ip-check -> secondaries (reason 'none', managed-type: 'full')
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3012] device (usb0): state change: secondaries -> activated (reason 'none', managed-type: 'full')
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3017] device (usb0): Activation: successful, device activated.
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3021] manager: startup complete
user@chupi:~ $ systemctl status NetworkManager
● NetworkManager.service - Network Manager
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; preset: enabled)
     Active: active (running) since Wed 2026-08-05 20:09:37 CEST; 9min ago
 Invocation: b3195f7be93546eaa5d200014e5a9b9d
       Docs: man:NetworkManager(8)
   Main PID: 954 (NetworkManager)
      Tasks: 4 (limit: 4915)
        CPU: 548ms
     CGroup: /system.slice/NetworkManager.service
             └─954 /usr/sbin/NetworkManager --no-daemon

Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3017] device (usb0): Activation: successful, device activated.
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3021] manager: startup complete
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.4351] device (wlan0): state change: activated -> deactivating (reason 'user-requested', managed-type: 'full')
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.4370] audit: op="device-disconnect" interface="wlan0" ifindex=4 pid=1327 uid=1000 result="success"
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5025] device (wlan0): supplicant interface state: completed -> disconnected
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5026] device (p2p-dev-wlan0): supplicant management interface state: completed -> disconnected
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5028] device (wlan0): state change: deactivating -> disconnected (reason 'user-requested', managed-type: 'full')
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5030] dhcp6 (wlan0): canceled DHCP transaction
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5030] dhcp6 (wlan0): activation: beginning transaction (timeout in 45 seconds)
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5030] dhcp6 (wlan0): state changed no lease
user@chupi:~ $ systemctl status NetworkManager
● NetworkManager.service - Network Manager
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; preset: enabled)
     Active: active (running) since Wed 2026-08-05 20:09:37 CEST; 10min ago
 Invocation: b3195f7be93546eaa5d200014e5a9b9d
       Docs: man:NetworkManager(8)
   Main PID: 954 (NetworkManager)
      Tasks: 4 (limit: 4915)
        CPU: 553ms
     CGroup: /system.slice/NetworkManager.service
             └─954 /usr/sbin/NetworkManager --no-daemon

Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3017] device (usb0): Activation: successful, device activated.
Aug 05 20:09:46 chupi NetworkManager[954]: <info>  [1785953386.3021] manager: startup complete
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.4351] device (wlan0): state change: activated -> deactivating (reason 'user-requested', managed-type: 'full')
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.4370] audit: op="device-disconnect" interface="wlan0" ifindex=4 pid=1327 uid=1000 result="success"
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5025] device (wlan0): supplicant interface state: completed -> disconnected
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5026] device (p2p-dev-wlan0): supplicant management interface state: completed -> disconnected
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5028] device (wlan0): state change: deactivating -> disconnected (reason 'user-requested', managed-type: 'full')
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5030] dhcp6 (wlan0): canceled DHCP transaction
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5030] dhcp6 (wlan0): activation: beginning transaction (timeout in 45 seconds)
Aug 05 20:18:01 chupi NetworkManager[954]: <info>  [1785953881.5030] dhcp6 (wlan0): state changed no lease
user@chupi:~ $ system status ModemManager
bash: system: command not found
user@chupi:~ $ systemctl status ModemManager
○ ModemManager.service - Modem Manager
     Loaded: loaded (/usr/lib/systemd/system/ModemManager.service; disabled; preset: enabled)
     Active: inactive (dead)
user@chupi:~ $

Julio.Cerveza · August 6, 2026, 6:56am

is it possible to record some logs from EG800 ?

as when my inet is getting lost, I cant even type any AT commands towards modem, no reaction, except the exit command CTRL A/X which seemst to work…

Saarvish · August 20, 2026, 8:17am

Hi @Julio.Cerveza

For the reported issue, please try the following steps:

Fix steps 1:Restore Proper USB Network Mode

Connect to the modem’s AT command port, run AT+QCFG=“usbnet”,0 to switch to the RMNET mode
Power cycle the modem, it will now be detected in NetworkManager
The missing DNS issue will resolve automatically once the interface is registered in NetworkManager

Fix step 2:Verify NetworkManager Dependencies

Ensure all required packages are installed on your Raspbian 13 system for proper modem management

Fix step 3: Resolve the DNS Issue

If you still experience DNS problems, verify your PDP context is activated: AT+QIACT?
Check DNS server addresses assigned by your network: AT+QIDNSCFG
If the DNS addresses show as “0.0.0.0”, reactivate the PDP context:
AT+QIDEACT
AT+QIACT
Or manually assign valid DNS servers:
AT+QIDNSCFG=1,“8.8.8.8”,“8.8.4.4”

Regarding the issue where the modem becomes unresponsive to AT commands when the network connection is lost, could you please confirm whether you are still experiencing this issue? If yes, please let us know, and we can proceed with further investigation.