What may help to debug the issue is a Wireshark capture of what
happens on this Ethernet connection.

> previously these tools will work.

What have you changed for it to stop working?

./usrp_burn_mb_eeprom --key=gpsdo --val=internal

this command will success, i'm reboot device and uhd_usrp_probe and usrp_burn_mb_eeprom broke.

ps. where i can read about dbg port?