Posted: Sat Feb 08, 2025 23:25 Post subject: Netgear Nighthawk R6700v2 possibly bricked?
Hello,
I decided to flash DD-WRT onto my R6700v2, after discovering it was supported. I did a regular reset of the router, flashed to factory-to-ddwrt.img from Downloads › betas › 2025 › 02-02-2025-r59468 › netgear-r6700v2
I then waited several minutes, and the router started lighting up most of the lights with both the red/orange and white LEDs, which I'd never seen before, it would cycle through all the ports, and the power light would stay the red/orange. It subsequently seems to cycle off and back on to repeat the process.
I fear I may have bricked it, though I hope I haven't. I did try the 30-30-30 reset with no luck. I guess I could give that a go, but I was hoping someone might be able to share some advice.
This is not my first run with DD-WRT, though it is the first with this particular router, and it has been several years.
Current release is a bad build, as noted going back a few builds. 59045 may flash, or not. No feedback, no reports in build threads to go by, and lack of reporting by the community leaves us guessing.
Put the file and program nmrpflash in the same directory. Rename the firmware file to something simple like d.chk
Set the computer's IP address to 192.168.1.10 subnet will fill itself automatically with 255.255.255.0
Then gateway as 192.168.1.1
I would put the flash program and its firmware in a folder in root of the drive. Like C:\netgear
Open a command prompt with administrator access.
type in cd C:\netgear
You should now be in the folder where the flash program is and firmware file.
Type in nmrpflash -L you need to know the network adapter's name mine for example was net14
nmrpflash -i "name of ethernet port here" -f d.img
mine for example would be nmrpflash -i net14 -f d.img
Press enter. Then power on the bricked device. It will start the flashing process once the link comes up. Wait until it says to reboot the router when done.
Much more easier than using the USB serial to pause the boot process and invoking the flash routines.
Here is a tip if you want to try different versions of dd-wrt to see which one works use the factory to DD-wrt files with this program it will accept it.
I appreciate the info, but kernel-panic69 already mentioned nmrpflash - good news, though, it worked, and I've subsequently gotten build 59045 installed.
If I'm reading what you've said correctly, you're suggesting using nmrpflash to install ddwrt to see if it works? I actually tried that, but I kept getting hit with a TFTP block rollover. From my limited research, it looks like this is due to my device likely have a size limit on TFTP files. The built in flashing method works, thankfully.
I will say that I'm not entirely sure what the most recent version I could flash actually is (I might experiment a bit more). I feel like I'd tried flashing 59045 from the Netgear firmware, only to have it soft-brick, but upgrading from an earlier build worked. It's also possible I made some other mistake, or am misremembering what I'm doing. I'll try and document what I'm able to find out. Thankfully, I've got 2 Ethernet ports, so while I get this sorted, I can still use the internet on this PC.
Can you point me to how I might capture that output? I'd be more than happy to provide it, currently I'm still going through trying to confirm r59045 is the last functional build.
Joined: 08 May 2018 Posts: 16050 Location: Texas, USA
Posted: Sun Feb 09, 2025 23:58 Post subject:
You have to open up the router, locate the serial UART header, figure out the pinout of the header, connect a USB-TTL-serial adapter to your PC and install / configure PuTTY or similar program to read data from the USB-TTL-serial adapter.
Oh, damn, in that case, maybe I'm not up for providing it lol
I've encountered a rather bizarre issue in my testing thus far, though. I managed to get up to r59093, but then, after setting up a username and password, when I went to the administration page, it would ask me for a new username and password, one that didn't match what I'd set, or anything I'd set prior. Subsequently, even if I flashed to stock firmware, and switched to a previously functioning version of ddwrt, this password prompt wouldn't go away. The only way I got it to go away was to hard reset the router. Unfortunately, doing this with 30-30-30 seems to be sporadically effective... I got it to work once, but since then it's been annoying.
Joined: 08 May 2018 Posts: 16050 Location: Texas, USA
Posted: Mon Feb 10, 2025 2:02 Post subject:
Sounds like a password manager is involved and/or you enabled info site password protection. It's usually more hassle-free to use a portable browser in private / incognito mode without any extensions loaded.
malcalevak wrote:
Oh, damn, in that case, maybe I'm not up for providing it lol
