Hello all! This time, i'm coming for the core problem

We're having an issue with stability that has many strange symptoms and has us all wondering what might be behind it.

Basically, we have a routerboard that reboots itself every few days. It can go up to a week, then reboot, or maybe reboot twice in a few hours.

Also, sometimes, when logging in via winbox the router takes a hefty time to respond. So, basically, i suspect of a hardware problem, because we have tried many configurations, connecting different clients, etc, and were never able to duplicate the problem.

I suspected first of the voltage, as the tower is on a mountain and using solar panels, so we checked the voltage almost every hour for a few days, and found out that we have a cycle, with max 4 volts variation between night/day, but it is always within specifications. So we discarded voltage.

Then i suspected of possible humidity condensation, but the RB is in a stanc(sealed hermetic) box, so that is not possible.

I also suspected interference, but there are no cell towers or other wi-fi towers in the area

I suspected of possible auto-interference between other antena we have on the same tower, but they are separated by a grounded grid that stops them from interfering each other.

In our logs we also had the infamous "unicast key exchange timeout" and we suspected it might have something to do with the issue at hand,, but after solving the Wep/wpa/tkip/ etc. it has never appeared again, yet the issue of reboots, persists

To check in depth for temperature, state of the cable, etc, we would have to take a trip to the mountain, wich means renting a VERY expensive helicopter and a few hours of hiking, or taking a 3 day long hike. So it would be awesome if there was a way to solve this without actually going there

I thank you in advance for your time, and if there is any additional information you might need to help me, please do ask, i can provide anything you might neeed.

Cheers

I`m not pretty sure, but when that happened to me with some 433 ah, all times the problem was related with capacitors.

It's is related with older boards but by the way take a look at this thread:

http://forum.mikrotik.com/viewtopic.php ... 33#p128229

Hey, interesting info there I have checked, and it seems this one is likely to be the cause. Is there some sort of record of serial-numbers of boards that have this issue?

Cheers Thanks very much for your time and help

I dont know if exist any list with s/n of affected boards, maybe support@mikrotik.com can help you...

An easy way to identify that boards is looking C828 capacitor. If its 6.3V 560µF and green/gold you got the bad one. New boards are
using a 6.3V 680µF in black/grey color.

I had issues with my RB433UAH, which was rebooting for no reasons every.... say 30~60 minutes...

In the end it was the "Power supply" issue.... because I had a 750GL, I tried and swapped the power supply, and realized that was the issue.

Went out to get 2 extra Power supply and threw the "not working too well" unit....

Can't afford to have unreliable Power supply.

Not sure if it is the same, but no harm trying.

Eric

I dont know if exist any list with s/n of affected boards, maybe support@mikrotik.com can help you...

An easy way to identify that boards is looking C828 capacitor. If its 6.3V 560µF and green/gold you got the bad one. New boards are
using a 6.3V 680µF in black/grey color.

Looks like a trip to the mountain is in order then

Thanks for4 the info man, how do you keep all those awesome info in your brain? it must be like 5 times the size of a normal person

Solved! And i got to ride in a chopper

Cheers, thanks for your time and patience