ORBI RBR50 firmware appears corrupted after circuit breaker was flipped

The commands below are particular for my Orbi RBR50.  Adjust to your model, firmware level, and sticker information from your device.

PUTTY and NMRPFLASH to FIX RBR50 ROUTER (Feb 2023)

Summary: RBR50 failed after power reset.  Load is corrupted, and no factory reset trick restored it.  No router, no wireless, no ethernet LAN communication, and no IP address.  Last resort was to connect a PC to the RBR50 serial line, manually set a few parameters in the boot loader (UBOOT), then use NMRPFLASH to upload a new image to the router through a router LAN port. You have to open the RBR50 case (two T10 screws) and remove the RBR50 interior (4 more T10 screws) and flip it over to get to the serial line.  Do NOT mess with the antenna or take anything else apart!  You need a $12 serial cable (Amazon worked for me). 

OTHER PERTINENT LINKS:

Solved: Re: Is my 13-month-old RBR50 bricked? Update: UN... - NETGEAR Communities will help you open your router and provide good info up to tftp (which did not work, since I had no IP address to use).   https://www.snbforums.com/attachments/RBR50-serial-port-pdf.23898/ is a pdf file of useful pics of connecting the  serial line.

PUTTY CONNECTION:

I purchased a serial cable from Amazon to connect to the RBR50 serial input.  I downloaded and installed Putty for Windows. Plug in the USB side of the serial line to PC, and use your Windows device manager to determine the COM line to use. (Mine was COM5).

Next, open a Putty Session to the Configuration Page, and configure it to talk to the RBR50.  I ultimately saved these settings in “RBR50RBR50” so I could bring it up a lot quicker. 

Session:

Serial line: COM5

Speed: 115200

Connection type: Serial (Telnet)

    Logging: (optional)

               Printable output

               Configured log file name with date and time in the name.

Connection:

     SSH:

Serial:

               COM5, 115200, 8 data bits, 1 stop bit, no Parity

Start the real work:

1. Break open the router carefully and expose the serial input and connect your serial cable to the PC and the unplugged or turned off RBR50.
2. Launch putty session by clicking OPEN
3. Boot the router. You should start to see output in the Putty session.  It will boot for a few seconds and then pause with “Hit any key to stop autoboot”. You have 2 seconds to press any keyboard key to stop the rest of the boot process.  Just reboot if you miss the 2 sec window and try again.
4. I set the following parameters.  You should not have to do this more than once.  I do not know if all of these were necessary except for the HW and Board ID, which I needed to read from the first firmware upload attempt, but they didn’t hurt.
   1. macset wan 14:59:c0:4c:57:62 (use the MAC on the bottom tag of the router)
   2. macset lan 14:59:c0:4c:57:63 (added 1 to wan MAC; I think it’s needed, since this is the interface I’m going to load the firmware to)
   3. board_model_id_set RBR50 (this one is necessary)
   4. set SSID ORBI58 (from bottom sticker)
   5. set passphrase (network key on bottom of RBR50)
   6. board_data_set 1201 (this appeared to reset to 120101 on reboot, even if I changed it; I don’t know what this number is.)
   7. board_hw_id_set LONG STRING OF DIGITS – BUT YOU HAVE TO ATTEMPT LOAD OF THE FIRMWARE FIRST (keep reading)

Configure and use NMRPFLASH to upload firmware

Download and extract NMRPFLASH.exe to an easy place to run it GitHub - jclehner/nmrpflash: Netgear Unbrick Utility.  There are good instructions on that site for use (scroll down).

Next, go ahead and connect your PC to the second ethernet port from the leftmost port (it’s the first LAN port).  Then, run the following command on your PC, which will tell you which device to use.  It was “Ethernet 3” connection and is called “net17” on my computer.

C:\Windows\System32> nmrpflash.exe" -L

net11  192.168.1.6      ac:12:03:25:85:f0  (Wi-Fi)

net17  169.254.70.43    00:c0:ca:a9:17:9c  (Ethernet 3)

Next, use this sequence to attempt the upload to RBR50. You should already have gone to NETGEAR support and downloaded the latest firmware for your router.

• Turn off the RBR50
• Run this command (Replace “RBR50-V2.7.4.24” below with the path and name of the file you need to upload):

nmrpflash.exe -i net17 -f RBR50-V2.7.4.24.img

• Turn the router back on as soon as you see NMRPFLASH write “waiting for Ethernet connection”.
• Come back and repeat this sequence after correcting the HW ID error (and any others, if they appear). Once the errors have been corrected – the router should boot and should be functional.

The first time you upload, you will get at least one error message:

Firmware Image HW ID do not match Board HW ID

In your Putty session (snippet below), look near the bottom for the HW ID in the image, and set the HW ID on board to that string, in my case:

board_hw_id_set 29765352+0+4000+512+2x2+2x2+4x4

Putty log file from first attempt at upload:

        [lots of dots ..................]

Done!

Bytes transferred = 49285249 (2f00881 hex)

TFTP upload done

Ignore Magic number checking when upgrade via NMRP,Magic number is 27051956!

mmc_read will run command: mmc read 0x871cf488 0x2a22 0x100

MMC read: dev # 0, block # 10786, count 256 ... 256 blocks read: OK

HW ID on board:

HW ID on image: 29765352+0+4000+512+2x2+2x2+4x4

Firmware Image HW ID do not match Board HW ID

Board HW ID mismatch,it is forbidden to be written to flash!!

Finally, repeat the sequence above (keep the Putty session open as you cycle power to the router; more convenient).