Hi there, I followed the guide at https://openwrt.org/toh/ubiquiti/unifi_6_plus. After reboot, I've been stuck in a tftp loop (Flashing White-Blue-Off - The device is in TFTP mode), unable to boot even the manufacturer's firmware.
I assume that the only way forward now, given that I cannot get past the tftp loop, is to crack open the case and use the serial port available on the inside. I'm not worried about the warranty (I already voided that) but the hardware is waterproofed and it is, apparently, annoying to get into. Let's assume that I can get in, get serial started, etc. Is there a specific guide for recovery that I should read?
After breaking open the box, installing a serial header and using Raspberry Pi's probe, I was able to use tftp to load the openwrt image and then do the whole installation again.
My best guess is that I missed 'echo 5edfacbf > /proc/ubnthal/.uf' - or it didn't work. This updated the SPI flash but because the other files weren't copied (either silently failing or, because this was my 3rd time doing it I didn't read the error messages) the router is trying to boot openwrt which doesn't exsit. Then it reboots into the tftp recovery which, of course, is doomed to failure. The cycle repeats and there is no way to fix this except by cracking open the case and doing the serial thing. Ho hum.
It's also possible that I entered all the commands correctly but without much delay
Because the commands after it fail silently, I didn't notice. I remember that, at the time, I rechecked all of them. Hence my confusion when it didn't work as expected. running
$ mmc writeprotect user get /dev/mmcblk0
> Write Protect Group size in blocks/bytes: 16384/8388608
> Write Protect Groups 0-465 (Blocks 0-7634943), No Write Protection
The "No Write Protection" means it's safe to proceed with the other commands.