Issue on core os/HAOS ? ... when adding USB 3/4G modem

hello cannot reach app over IP after 3G modem being plugged on my RPI5
this is similar on other pi without HAOS But blocking for HAOS

explanation: when adding this modem on usb , main os add a network device called usb0 and become a default route and 1st responder to request ( routing) so HAOS seems unreachable
after rebooting usb0 network device does not appear on network menu for me to enable ( after the modem being unplugged as it s a booking point)

on regular RPI , workaround is to launch ifconfig usb0 down and delete related default IP route

normal situation should be aourond that
any unknown or additional hot pluggable network card should be disabled ,registered on haOS and manageable (without route being added as default)

i don’t know to solve on core os or haos
do you have some quick test or solution for that? ex managed with rc.local service on any layer?
best regard

What other USB devices do you have connected?

Do you have Static IPs configured on your network?

Nadhat GSM MK2 - 4G / LTE - USB et HAT - SimCom A7682E

plugged on usb

Module GSM 4G / LTE

  • Connectique: USB ou GPIO
  • Interface: UART, USB, Mic., Audio out
  • Reseau: GSM/GPRS, Edge, LTE.
  • Commande AT
  • Nano SIM

no configuration done for usb device , my rpi with has is on eth0 static ip+wifi with dhcp ( in same network ) , my definitive config
should be eth0 by default ,wlan0 dhcp for internet connection failover, usb0 never as default route except if i manage…
the goal is to have resilient networking for at least send a sms and notification to compagnon app

as other usb devices : just a Zigbee dongle ( pizigate with usb converter between) but it does not provide ip connection

HAOS is a closed operating system and there is likely no drivers for that hardware. It not likely to be added if there isn’t any.

I suggest switching to container install, and attaching this hardware to the host OS…

If you want to request the hardware be added, the path is here, but I would expect a no as not many people have this hardware and your changes would be there for all users. home-assistant · Discussions · GitHub
The OS is designed to be as lightweight as possible to be able to run on minimal hardware configurations. Since in HAOS you have no control over the OS itself, you cannot install extra things.