Hi

I was playing with bridging NAT and switcher ports on the rother (was trying to make ipv6 working) and router began to reboot again and again in cycle. So I turned it off, and then when turned it on again I can't access it anymore. ACT button isn't flashing at all (don't remember if it was while router was working ok). Port led is blinking when cable is connected to the port.

Tried reset button/jumper - no success: when turned while holding RES button, ACT button turns on and stays like this forever. With jumper shorted nothing happens at all.
Also monitored network card with wireshark and seems like it doesn't receive anything from the router.

Anyone have any ideas how to make it work again?


Thanks

Tried to solder reset point (jumper) because it's unable to short it with something for long period of time. Now ACT led is turning on with PWR led and keep lit. Still can't see it in netinstall. I assume flash become damaged somehow. Sad I have no console cable to see the console.

Noticed ports are working as hub now, can see all traffic from wan cable.

Sad mikrotik doesn't have stronger software restore procedure for such situations.

I assume flash become damaged somehow.

Sad mikrotik doesn't have stronger software restore procedure for such situations.

You are denying yourself. How to restore software in case of hardware failure?
If you can't Netinstall this RB751G, just RMA it.

Regards,

I assume flash become damaged somehow.

Sad mikrotik doesn't have stronger software restore procedure for such situations.

You are denying yourself. How to restore software in case of hardware failure?
If you can't Netinstall this RB751G, just RMA it.

Regards,

Well, as you can see even RouterBOOT is damaged here, so it's a design problem. It should be something like bios on PC motherboard, which is separated from other flash memory (which is probably damaged in my case).

Worked 4 months for me, warranty term was 3, so I can't RMA it to the local reseller.

Regards

Today's the nice day!

Managed to unbrick my 751G-2HnD somehow (was playing with nand/flash pins with screwdriver, noticed it can start blinking with ACT when shorting some pins on flash when RES is pressed and ACT is gonna light - 1 sec after power/reset), probably some crc calculation went wrong and router started to blink with ACT led (few times it hanged with blinking) and probably restored default config, because then I could login with Winbox. After this it started to work normally like before the incident. Pressing RES button is working again for restoring default config or netinstall (when pressing longer). But with netinstall after loading latest routeros status never went to "waiting reboot", it just went to "Ready" again, and after manual reboot it wasn't updated. So I don't know if netinstall is working for me, updated it in normal way.

Interesting how long it will work from now on.

Today's the nice day!

Managed to unbrick my 751G-2HnD somehow (was playing with nand/flash pins with screwdriver, noticed it can start blinking with ACT when shorting some pins on flash when RES is pressed and ACT is gonna light - 1 sec after power/reset), probably some crc calculation went wrong and router started to blink with ACT led (few times it hanged with blinking) and probably restored default config, because then I could login with Winbox. After this it started to work normally like before the incident. Pressing RES button is working again for restoring default config or netinstall (when pressing longer). But with netinstall after loading latest routeros status never went to "waiting reboot", it just went to "Ready" again, and after manual reboot it wasn't updated. So I don't know if netinstall is working for me, updated it in normal way.

Interesting how long it will work from now on.

Can pls post pics of the pins and i would like to abuse and ask u make a tutorial for this i have 2 dead the same way.

Today's the nice day!

Managed to unbrick my 751G-2HnD somehow (was playing with nand/flash pins with screwdriver, noticed it can start blinking with ACT when shorting some pins on flash when RES is pressed and ACT is gonna light - 1 sec after power/reset), probably some crc calculation went wrong and router started to blink with ACT led (few times it hanged with blinking) and probably restored default config, because then I could login with Winbox. After this it started to work normally like before the incident. Pressing RES button is working again for restoring default config or netinstall (when pressing longer). But with netinstall after loading latest routeros status never went to "waiting reboot", it just went to "Ready" again, and after manual reboot it wasn't updated. So I don't know if netinstall is working for me, updated it in normal way.

Interesting how long it will work from now on.

Could u pls post a picture with the pins u shorted and i would like to abuse and ask for a tutorial i have 2 router bricked.

Can pls post pics of the pins and i would like to abuse and ask u make a tutorial for this i have 2 dead the same way.

Your 751G-2HnD also working like switch only and ACT led is keeping light after reset button is hold?
Can't do tutorial because I'm not sure what exactly I did and what actions exactly made it alive again, but here are some points:

1. Hold reset button all the time (maybe you can use reset pad for this, but it's hard to short it with anything except soldering, so I was just holding reset button).
2. When you connect power (and reset button is hold), ACT button should start lighting after 1-2 sec. Try to short some pins for a short time exactly at that time when ACT is going to be lit.
3. I was shortening pins with a thin thing, so probably only one pair was shorten at the same time.
4. Once or twice I was able to make ACT button start blinking (but it continued blinking forever, so no luck was at that time). Basically this blinking made me curious and wanted to continue.
5. Instead of removing and reconnecting the power cord (it can be annoying when doing this again and again) you can try to short some pins (don't remember which exactly) for a short time and router will reset.
6. Probably you want to connect router's 1st port to your PC to monitor traffic (I used wireshark) and see when it become alive again (in netinstall mode). But in my case it was like it just restored its original configuration, blinked with all port leds and start working.
7. Attached image of the flash I was playing with.

IT'S ALIVE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

thank u for taking the time!!!!!!!

IT'S ALIVE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

thank u for taking the time!!!!!!!

Maybe you can make some tutorial now?

You explanation was better than any tutorial... am to scared to open up this 2 routers , i will wait for another dead one and post tutorial. thank u for taking the time.