Support for ADB VV3220

Hi, My netwrok operator give me four modem ADB VV3220
completely blocked. They have changed the default password (admin, admin or user, power) and are not even able to change the ip address to the modem. Turning on the internet I noticed that these modems are based on openwrt and I thought about writing on your forum. Three of the four managed to reset them to the factory settings with the 30-30-30 method but with this I can not in any way. I connected in serial and I noticed that the CFE allows only some commands (does not allow the reset nvram).
I can not even find another firmware and ADB refuses to provide it..
I am attaching the serial boot logs, the commands available in CFE.Thanks a lot to all !

BOOT LOG: https://pastebin.com/itg2e81D
CFE: https://pastebin.com/EGrHmQkK

Looks like bootloader will support booting from tftp, assuming you can find/make an image for it.

But this line Verifying kernel signature... makes me think its probably a lost cause, since i dont think there is any way to satisfy that check . The only way would be to rewrite the bootloader which is not a trivial thing to do..

Instead
Id suggest getting a good device (8+ mb flash / 64+ mb ram), and running it as a client of the isp’s device.

(Isp’s router) lan1 == wan(your router)lan ports/wifi

  • Its true youd probably be running with double nat , but it shouldnt be a deal breaker unless youre wanting to do something fancy.. the performance should be good enough. (Test connecting directly to isp router, and then with the openwrt device inbetween if you suspect any speed problems.)
  • this approach separates your internal lan devices from the isp
  • you could set up a vpn on your own opwnwrt device and tunnel anything that the isp is blocking (but if they are id strongly consider going with another isp)

https://openwrt.org/docs/guide-user/network/integrating-lede-introduction

https://openwrt.org/docs/guide-user/network/switch_router_gateway_and_nat

Edit: adding this awesome top10 device summary by @slh
Top ten routers currently in use?

Thanks a lot for the fast reply. Another question:
would it be possible to dump the firmware from the same unlocked and functioning modem (shell access) and boot via tftp on the locked one? Thanks !