Posted: Wed Mar 24, 2021 19:26 Post subject: R7800 and TFTP
Hello,
I'm in the process of gathering info to upgrade my R7800 built from r41813.
So far with all my dd-wrt installs, I've not had to do anything like Restore etc.
But now looking at several posts that talk about R7800 issues with newer builds, i just thought it might be helpful to be prepared in the event I need to restore.
The question is - While using the process to restore what firmware should I restore to? My old dd-wrt that was running fine? Or Netgear?
[quote="blkt"]Save a copy of your r41813 configuration via webUI Administration -> Backup so if you ever decide to flash
r41813 again in the future you can restore the backup without manually reconfiguring everything.
WebUI or CLI Flash is dd-wrt-webupgrade.bin and TFTP recovery mode is factory-to-ddwrt.img your choice.[/quote]
ok, so just to clarify, if in the off chance that I need to restore a bricked/not working dd-wrt, I need to use factory-to-ddwrt.img file from my r41813 when using TFTP Client to restore.
Then, I can use the backup configuration file to go back to state prior to upgrading.
I had to restore the Netgear firmware via tftp to unbrick my router. Then I had issues with trying to do the factory-to-dd-wrt flash from the Netgear GUI - it would not take the latest one for r46130. After unbricking again, I ended up having to flash it with the factory-to-ddwrt firmware for r42278 via tftp. Then I used the dd-wrt gui to upgrade to r42251. But when I tried to upgrade to r46130 using the dd-wrt gui the router got bricked. The other 4 R7800 routers had no problem with upgrading to r46130. Since they are all the same version, I wonder what the problem is.
Did you configure it to use vanilla wireless interface firmware before trying to flash any builds past 46069?
They are all using vanilla. Only this one router is "broken". Right now I'm testing upgrading from r45592 so this'll take awhile to see what happens.
More info. The router worked OK with r46069 but bricked with r46130. There is a filesize difference but I don't know if that's the issue. r46069 is 31338496 bytes while r46130 is 31428608 bytes.
After unbricking the router I gave that a try and it seems to have flashed OK. Must have been the filesize? I'll have to manually configure this now. It's a good thing it's predecessor didn't brick my other routers.
I had to restore the Netgear firmware via tftp to unbrick my router. Then I had issues with trying to do the factory-to-dd-wrt flash from the Netgear GUI - it would not take the latest one for r46130.
normally you don't need to flash back to stock either
i would have directly flashed build r46069 or r46177 (factory-to-ddwrt.img) via TFTP (as debricking)
I just read through that thread. Apparently it was something to do with filesize. It's interesting that it bricked only one of my R7800 routers.
ho1Aetoo wrote:
Quote:
I had to restore the Netgear firmware via tftp to unbrick my router. Then I had issues with trying to do the factory-to-dd-wrt flash from the Netgear GUI - it would not take the latest one for r46130.
normally you don't need to flash back to stock either
i would have directly flashed build r46069 or r46177 (factory-to-ddwrt.img) via TFTP (as debricking)
I was unable to recover via tftp through the LAN port (you know, the brief time when you get a ping response after rebooting). I opened up the box and connected my serial port adapter to the J1 header and still couldn't flash the factory-to-ddwrt image (something to do with bad format). Anyway, the only way to recover was to tftp flash the OEM firmware via the serial port and then do the factory-to-ddwrt flash. I couldn't even flash the factory-to-ddwrt firmware using the Netgear GUI but was able to use tftp to flash it via the serial port. Hopefully, I explained it well. Anyway, however, I got the router working again and flashed it with r46177. All is good with the world again.
(you know, the brief time when you get a ping response after rebooting)
no i don't know actually, if you put the router in recovery mode properly then it sends ping replies for hours and waits for a TFTP upload
Somewhere there was a procedure that said when you boot a bricked router you might see ping responses from the ethernet port for a brief period of time which is suppose to allow you to upload the firmware via tftp at this time. But you have to be quick. tftp via the serial port was easier but you have to open the box and connect a serial port cable - just have to know what the pinouts on the serial port header are. I see someone wrote a procedure using Windows to get into the R7800 routers CLI - I'll have to try that next time.
1 Turn off the power, push and hold the reset button (in a hole on backside) with a pin
2 While still holding the reset button, turn on the power, and the power led starts flashing white (after it first flashes orange for a while)
3 Release the reset button after the power led flashes white (for at least 10 times), execute the tftp command on your computer. (Note: There is no requirement to wait for 10 flashes although Netgear apparently says that in official advice. You can release the button once it starts to flash white (after the orange flashing if over).)
4 The power led will stop flashing if you succeeded in transferring the image, and the router reboots rather quickly with the new firmware.