Hi.

Can I flash ROS image on RB with netinstall without using the RS232 to configure boot from ethernet ?

Sometimes Happen to damage when updating the ROS from the WLAN.

Alternatively, is there any option to change RB booting to: once boot from ethernet after boot from NAND? or something like that without RS232?

There is no such option?

There is a chance to add this option to ROS bootloader: If the long hold down the reset (10 sec) then RB boot from ethernet

The available options are:

• ethernet
  flash-boot
  flash-boot-once-then-nand
  nand-if-fail-then-ethernet
  nand-only
  try-ethernet-once-then-nand

I normally get it by starting net-install and holding reset while power cycling then it net-boots...