I updated the firmware on an RB2011 today, I think the version that was on it was 6.23, I updated to 6.42.6. After the unit rebooted, it never fully came back up. The LCD on the router just showed "MikroTik" and the unit was unresponsive, I couldn't ping it, the touch screen would not change... so I unplugged the unit after waiting about 1 hour and plugged it back in. Same thing, no response, so I pressed the reset button while the unit was unplugged and held it while plugging the router in. The router boots up fine this way, and it looks like it kept the config it had, and the firmware is now updated, but if it ever looses power, it will need to have the reset button pressed while powering it on to get it to boot. has anyone else experienced this is there a good solution to fix this issue?

From 6.23 is a big jump and if I recall correctly, there is an intermediate upgrade version to be done before latest from a big jump like that.

My best suggestion will be to backup config via export, then redo with 6.42.6 via netinstall and import the backup config again

Thanks, I will give that a try tomorrow morning and see what happens. The link is in use from about noon until 8:00 PM, so I have to work around those schedules.

In other topics, similar behavior was mentioned by NathanA and Normis, both concluding that pressing button cause use of backup bootloader in case when main bootloader is corrupted.
This seems like exact match, so I believe CZFan is right - do netinstall to fix corrupted bootloader.

I would like to add that since 6.23 there were some BC breaks in config (typically bridge setting does not have master port anymore etc...) and your current config after migration might not truly reflect original config on 6.23 . It might be good to check this closely.

Correct, if reset button is pressed while power is applied, backup bootloader is used instead of main bootloader.

If RouterOS boots fine when you do this, what this actually tells us is that it's the bootloader that is corrupt, not RouterOS. And Netinstall does not fix the bootloader. So Netinstalling is *likely* not going to help.

What you need to do is re-flash the main bootloader. This is very easy to do: get RouterOS booted by using the reset button to engage the backup bootloader, and then go to System > Routerboard > Upgrade. Then reboot after that to confirm it now works.

If it doesn't, as at least a temporary workaround, you can go to System > Routerboard > Settings and check Force Backup Booter. That way you can continue to use the router and won't have to always hold the reset button down every time you reboot it while you continue to research the issue.

Since this is a model that has a serial console, what *I* would do if the above doesn't fix it is attach a serial cable to the console port, and then see what RouterBOOT actually sends to the console during boot. It might give you a clue about what is going on.

-- Nathan

What you need to do is re-flash the main bootloader. This is very easy to do: get RouterOS booted by using the reset button to engage the backup bootloader, and then go to System > Routerboard > Upgrade. Then reboot after that to confirm it now works.

If it doesn't, as at least a temporary workaround, you can go to System > Routerboard > Settings and check Force Backup Booter. That way you can continue to use the router and won't have to always hold the reset button down every time you reboot it while you continue to research the issue.

That worked perfect, I guess I need to update both the OS, and firmware when I do updates.

In the recent versions you can select auto upgrade of the bootloader in System->Routerboard->Settings so you don't have to remember this.

Actually, it should have still booted up without the bootloader being updated. For proof of this, the "backup bootloader" version remains the same through the lifetime of the RouterBoard. It cannot be upgraded or overwritten. This is a safety precaution so that if the main bootloader becomes corrupt for some reason (failed update, etc.), you still have a bootloader you can use. This feature is *fantastic* as it makes RouterBoards almost brick-proof.

So what this means is that when you press Reset to access the backup bootloader, you are actually running an old bootloader version. And yet, despite this, your RouterOS booted up just fine with the backup bootloader. So old bootloader version is not a problem.

So the problem was not that you didn't update the main bootloader after RouterOS upgrade. The problem is simply that somehow, your main bootloader became corrupt. How that happened, I could not say.

-- NAthan

Thanks for correction. I didnt know that primary bootloader survives netinstall. I try to read as much as possible but every day, I can learn more and more

Actually, it should have still booted up without the bootloader being updated. For proof of this, the "backup bootloader" version remains the same through the lifetime of the RouterBoard. It cannot be upgraded or overwritten.

That is close, but not completely true. There exist some packages that you can install that really upgrade the backup bootloader. The use is risky but it is required
to update the backup bootloader to implement some of the security features that were introduced later in the development (the tricks with holding the button for
some exactly defined time to erase the config).