Hi, I have a netgear wax630 device and would like to install openwrt on it. Instructions seems understandable for installation part but I have a more generic question for how can I perform a full backup (existing firmware, bootloader, calibration, etc) of the device that came in from the factory before installing openwrt? Is this the general approach https://openwrt.org/docs/guide-user/installation/generic.backup ?