Hello Folks!

I have one old RB411 sitting at one customers for years without any issues, suddenly yesterday the device start to reboot in random intervals 3-2 minutes - 90 minutes.
The device uses RoS6.41.3, the last known working with wireless and NV2, ptmp environment.

I tried to upload bug fix only variants of RoS in the same era as RoS6.41.3 was actual, but it does not work either, I manage to transfer roughly 70-80% then the device reboots.
I tried to reduce transfer bandwidth, all the way down to 64Kbit/s, but the device still reboots after about the same time as with free upload speed.
The device CPU is 5-10% all the time as far I can see.

All other 4 devices in same sector works perfectly without any signs of problems.

Could this be some hardware error in the device or is it some weird thing regarding NV2 causing the device to just reboot ?

The device logs looks like this, here for the two upload attempts:
oct/28/2018 20:48:55 system,error,critical router was rebooted without proper shutdown
oct/28/2018 20:59:55 system,error,critical router was rebooted without proper shutdown

After years of service, my first guess would be power supply being marginal and heading towards worse.

Thanks!

It is powered by ubiquity UBI-US-8-150W which also powers 3 ubiquity unify access points, all of them are working perfectly and there is nothing in the logs indicating power problems, simply link down, link up when the RB411 restarts.

Update, I managed to get lates stable at the era, RoS6.0.46, into the RB411 by using fetch from it, fetching it from one of our servers, then it worked flawlessly and good speed to.
All attempts trying to do otherwise caused RB411 to reboot, strange.

I also managed to do system package downgrade, the device came back after some 30-40 seconds now with RoS6.0.46.
Downgrading firmware by a system routerboard upgrade, was also successful.

Now I have to wait sometime to see if the problems was caused by to high RoS version for the old old device.

Offcourse we will replace the customer device with DynaDish or similar, when we have the ability to access it physically.

Lets see now.

Hello Folks!

Update, the downgrade did not help, after some time the device started to reboot itself again.

It is either some problem with the ubiquity device providing power to the device, problems with the device itself caused by rb411 internal hardware or still to high RoS versions for the device. We have several RB411 with RoS6.41.3 that does not behave like this, so it is looks like the first two is most plausible here.

Problem with capacitors:
viewtopic.php?f=3&t=75405&hilit=rb411+capacitors

Problem with capacitors:
viewtopic.php?f=3&t=75405&hilit=rb411+capacitors

Thanks! Good hint!
I will do that check whilst on site. We have had if before, but at that time the devices were fully down.
Bad capacitors can well cause this.

I downgraded even further to 6.36.4, same still rebooting, so it is not likely the routers or firmware.

The device act so strange, if I try to do a supoutfile, the device crashes and reboot itself after some moments, reaching 2% or in best case 25%,
However, the board will be replaced the upcoming days, then we will see.

Hello Folks1

The RB411 board was replaced with DynaDish and customer is happy again.

It was the capacitors, they have leaked some brown stuff bin the tops which also was expanded a bit.
Replacing the capacitors and the device works perfectly again.