Netgear R7900 possibly bricked after flashing OpenWrt 21.02.3

My Netgear Nighthawk x6 R7900 router has been plagued by DNS issues of the OEM firmware for some time. I finally decided to try an open-source firmware, and downloaded OpenWrt from this page

I used the Netgear web GUI and flashed the openwrt.chk file, but then I am no longer able to connect to the router.

The router only has a single power LED on in red. If I connect my laptop to the LAN port, the LED of the port is led in white, but my laptop (running Ubuntu 22.04) could not get IP address via DHCP. I manually set IP address, but I could not ssh to or any other address in /24.

I tried pressing the reset button on the router, nothing changes no matter how long I press.

I read the failsafe wiki page, when turning on my router, my power LED never blinks. I don't know if it is in the failsafe state already, or bricked.

I was also trying to revert to the OEM firmware, but could not find any documentation on how to do this (given I could not see web GUI or ssh)

does anyone have similar issues? I am appreciated if you can help me fix this.

I don't know anything about that router but shouldn't your ip address be range?

from reading this page:

I was under the impression that the default gateway IP is and the default allowed IP range is 1.x, not 0.x. Because the DHCP did not work, so I did not really know what was the correct default range.

I just tried to manually request IP from 192.168.0.x, and set router address to either 0.1 or 1.1, but neither allow me to ssh to the router.

The reason i mentioned that range was because in your original post you said "".. Notice the 163 part.

sorry, that was a typo.

Was R7900's wan port connected to the lan port of ISP' router or modem? If it was, disconnect it and power cycle R7900. Then try to access R7900 via

@rwl408, no, the uplink (WAN) is not connected.

I guess the router is busted like you said. I don't have experience with R7900 although I used to have a R7000 loaded with DD-Wrt (and recently converted a R6700 to R7000). It seems that you need the CFE TFTP + serial recovery method according to the OpenWrt R7900 Techdata. From my understanding, R7900 is a Costco's version of R8000 so you can ask Netgear or DD-Wrt (supports R8000) forums for how to recovery from a bricked R8000/R7900 too.

Edit - Found this link in my browser's bookmark:
How do I upload firmware to my NETGEAR router using a TFTP client on Microsoft Windows?

sorry for my late reply - thanks for your comment again. I tried to connect to the router via tftp. This is what I did -

  • boot up the router (flashed with OpenWrt 21.02.3)
  • after flashing some of the indicators, the router shows only amber light on the top LED, no other LED is on
  • connect a laptop to the router with a wire to one of the 4 LAN ports
  • the laptop is set in DHCP mode (running Ubuntu Linux) - type ipconfig, shows that the laptop can't get DHCP address
  • ping, failed
  • set laptop to static IP (, still can't connect to

is there any other ways to connect or re-flash the router?


Yes, there is. Get yourself a TTL-Serial-to-USB-cable, open the router and connect the router via the cable with your PC.

It's said that the R7900 and R8000 are quite similar, so maybe this would help:

Also, please refer to:


I do hope it helps a bit.

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fangq, go to
This is the "Netgear Unbrick Utility".

I have the same router and the conditions you described were exactly the same as when I bricked my R7900. Do the NUU and make it great again! :wink:

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thank you so much @mechango, nmrpflash did the trick! I am happy that the router is finally working again.

it turns out timing is important for nmrpflash to work successfully - when turning on the router after launching the command, I first got an Timeout while waiting for TFTP_UL_REQ.

sudo nmrpflash -i enp2s0 -f R7900-V1.0.4.38_10.0.50.chk -T 20 -t 1000
Advertising NMRP server on enp2s0 ... /
Received configuration request from xx:xx:xx...
Sending configuration:
Timeout while waiting for TFTP_UL_REQ.

however, immediately relaunching the command could allow the file to be uploaded. even thought I am still getting Timeout while waiting for 0000. error, the router was able to finish rebooting and function again

sudo nmrpflash -i enp2s0 -f R7900-V1.0.4.38_10.0.50.chk -T 20 -t 1000
Advertising NMRP server on enp2s0 ... -
Received TFTP_UL_REQ while waiting for CONF_REQ!
Received upload request without filename.
Uploading R7900-V1.0.4.38_10.0.50.chk ... OK
Waiting for remote to respond.
Timeout while waiting for 0000.

thanks again!

Good job. BTW, at which point I bricked my router was when I tried to flash an OpenWRT to get to finally flashing a Fresh Tomato firmware. It failed on the OpenWRT stage. Can anyone help in flashing the Tomato onto a r7900?

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