Just adding to the conversation (and a few tips/tricks in case someone else is in the same boat and having trouble, here's background and a step-by-step of what seems to have worked for me to get the router booting again). I have two Belkin RT3200s that I put into service only about 4 months ago after doing a lot of research and seeing good things about stability/reliability on openWRT. I'm using the first as my router and providing wifi, and a second as a wired AP. (So this is distressing to know that I might just be a reboot away from a brick again.)
It appears that I had used the 1.0.3 installer, and I was running 25.05.0 and had not done any further flashes or upgrades, and the router had been running stable with uptime in the months.
On Sunday I was hit by the OKD. We had a power outage that day and I have my main RT3200 on a battery backup, so our internet was not interrupted during the 2-hour outage, but later I rebooted via the web while troubleshooting another issue with my VPN and the wifi/network never came back. I had no lights or sign of life upon pulling the power cord and flipping the on-off switch.
Stupidly, I had not backed up the factory or other partitions from the main device yet (yeah, no excuse).
I have downloaded the four mtd0-3 from the LuCi web interface, and scp'd the boot_backup OEM files from my 2nd working router now using the following method, and the files appear to be the correct sizes referenced above- I had seen references to using DD to image the partitions and backup but this method referenced on the dangowrt github under the backup stock vendor/bootchain section seemed easier and perhaps guide should be added to the wiki for this model?
#this is for my router which used the 1.0.3 installer and has UBI but not the newest 1.1.x changes
#from your computer, ssh into the router (terminal, putty)
ssh root@192.168.1.1
#make a directory and mount the boot_backup partition while SSH'd into the router
mkdir /tmp/boot_backup
mount -t ubifs ubi0:boot_backup /tmp/boot_backup
#use powershell to copy files from that folder to your pc in scp mode
scp -r root@192.168.1.1:/tmp/boot_backup C:\Temp\boot_backup
I tried cooling my OKD'd router in the refrigerator for an hour, and it did not boot successfully on its own (still no LEDs lighting up on the front). My 3.3v USB-serial cable arrived today, and was able to get the mtk_uartboot to boot the router up successfully (and the good news is that I was able to download all of the mtd0-mtd3 from LuCi, and I was also able to SSH in and save the boot_backup versions as well, so now both of my routers have current and original mtd backups!)
But even after trying multiple times, and it seems that when the mtk_uartboot command finishes running and kicks me over into putty.exe, the router boot has already happened, and I couldn't interrupt the process to get to the Uboot menu and rewrite the FIP.
The thing that worked for me was to control-C the mtk_uartboot shell when the following line showed:
FIP sent.
And switch to another command window where I had pre-pasted the 2nd part of the command and quickly hit return to run it:
putty.exe -serial COM3 -sercfg 115200,8,n,1,N
This dumped me into the serial shell with just 1-2 seconds left on the boot count-down and I was able to arrow down to the Uboot and run the command to re-write my FIP:
#in putty, since I did not run 1.1.1 UBI installer and was on 23.05.0, run command to re-copy the FIP
mtd read fip $loadaddr 0x0 0x140000 && mtd write fip $loadaddr 0x0 0x140000
So far, the router has cold-booted two more times successfully and I placed it back into service.
Here's hoping we get a more permanent fix soon.
