Even with nul modem to console rb433 boots normally but when prompt is presented for password it takes ample second for board to not accept input from console any more.

At best I come to "ad" but the "min" won't accepted any more. Where after some 10 secs waiting board just reboots.
Ethernet also is not working. Both netinstall or discovery won't see the board.

Have board reset by screwdriver method.
Board shows during boot:

RouterBoot booter 2.15
RouterBoard 433

Authorization: Passed
CPU frequency: 300 Mhz
Memory size: 64Mb

Press any key within 2 seconds to enter setup..
loading kernel from nand ....ok
setting up elf image... ok
jumping to kernel code
Starting...
Starting services....

####new screen####
MikroTik 4.16
MikroTik Login:

#### and that's it!

After this it just takes some 10 seconds for board to boot again. And this goes on and on and on and on etc....


Have nand

NetInstall it.

NetInstall it.

Even with nul modem to console rb433 boots normally but when prompt is presented for password it takes ample second for board to not accept input from console any more.

At best I come to "ad" but the "min" won't accepted any more. Where after some 10 secs waiting board just reboots.
Ethernet also is not working. Both netinstall or discovery won't see the board.

Have board reset by screwdriver method.
Board shows during boot:

RouterBoot booter 2.15
RouterBoard 433

Authorization: Passed
CPU frequency: 300 Mhz
Memory size: 64Mb

Press any key within 2 seconds to enter setup..
loading kernel from nand ....ok
setting up elf image... ok
jumping to kernel code
Starting...
Starting services....

####new screen####
MikroTik 4.16
MikroTik Login:

#### and that's it!

After this it just takes some 10 seconds for board to boot again. And this goes on and on and on and on etc....

I'm not sure what that has to do with my suggestion. Interrupt when prompted to get into the boot loader setup, set it to boot from network, and NetInstall it via PXE.

Or does it reboot from the boot loader menu as well? So far you've only indicated this happens once the OS is up.

I don't know what you exactly with "boot loader menu" but if you mean the menu presented in the consol connected via the nul modem then I can enter the different menus for setting different boot options and memory check, etc.
But whatever I do, as soon as the board has to boot it seems to load normally but after presenting the prompt it just reboots each time over and over again.

I tried netinstall but the board just doesn't boot over Ethernet. Nothing happens.
The only thing I can try tomorrow is to upload new software by Xmodem. But it takes hours and its late again!

I've seen this a number of times for various reasons:

1) I've had an few XR5 cards that failed and would cause an RB433 to reboot as soon as it finished booting
2) I've had a dozen RB600s do this after 1-2 years in operation (the capacitors were faulty on all the boards)
3) I've had a mix of different routerboards do this when the power supply was insufficient

Of course you can always just have an outright faulty RB433.

Does the board reboot itself after 10-20s if you leave it in the boot loader menu or only after booting the RouterOS from Nand?
Do you have any wireless cards in the board, or it is just a plain RB433, and with what and how are you powering the board?
When using NetInstall is the board registering the BootP server in the console?

Cheers

if it is rebooting at this rate you have several things you should do:

1) unplug all modules to see if bare metal is working;
2) reset configuration using reset hole
3) if bare router still reboots using null modem cable enter in bootloader menu and rep it for netinstall. when doing reinstall of software uncheck save old configuration

usually first one helps, if that is not the case, 2nd has quite high success rate to bring router back and 3rd helps if everything is ok with HW.

Just note all of this, if your problems did not start after software update. If that is the case, try to update bootloader using null modem cable.

Do the Ethernet LEDs light up at all? For example when turning on the device, or plugging in a cable? Or they are always off, even when rebooting?

Do the Ethernet LEDs light up at all? For example when turning on the device, or plugging in a cable? Or they are always off, even when rebooting?

I have the same problem, but now when i unplugged minipci cards, 4 leds (LD504, LD502, LD503, LD501) near minipci slots and the blue led near poe, lighten up and stay there. nothing else happens.

I tried rest, switched power supply, nothing changes.. just stucked there.

Any ideas whats wrong?

I see after my last post of 29 September I have had several replies to my topic I have not had any notification for. (This is a forum issue that is around for two years. Sometimes I get notifications, sometimes not. MT definitely needs to check on the engine responsible for that. I have several hundreds of topics started and sometimes I get not a single e-mail notification for a week just to find that several topics indeed have had new replies in that week. Since I am always very busy I thus 'forget' about some topics I started and thus am not replying to these.... )

Anyway, that specific rb411 was not able to update by netinstall neither. I believe the unit ended in the bin....
As I can remember, the led lights were indeed flashing like normal.
Like mentioned before, the board (completely empty, no cards attached) just booted normally but secs after it is finished it just boots again....

I might come back on this since I still have some other 4xx boards with issues that are on a stack for last attempt tests before they end in the bin as well. Just need to find some time to test them...

Do the Ethernet LEDs light up at all? For example when turning on the device, or plugging in a cable? Or they are always off, even when rebooting?

Same issue and Ethernet is always off, when trying to boot off of ethernet rather than nand, I get PHY Error, then it attempts to bootp and fails.

Any ideas where to start looking? I am guessing it could be the power regulator stage or similar?? have tried multiple power supplies and a ubiquiti 24V POE injector with the same result.
Are there any test points on the PCB that can check to verify the correct voltages etc.

What NAND and RAM chips are on the board? Are they DTC RAM?

We believe that this RAM is unreliable and causes NAND to corrupt. We have been able to recover some boards using Netinstall, but others are hosed up just as you describe. Even after reinstalling we see incremental NAND block failures until at some point the board will no longer boot.

We have had a dozen failures like this in the past month, all with the same RAM. That seems to be the common element.

We have sent all sorts of diagnostics to support with no help.

If you don't have DTC RAM, then it could be one of the other issues. Make sure you reset the board using hard reset (shorting the moon connectors).

No DTC. Nanya and Hynix.