711G-5HnD port Flapping up and down when static

RouterOS General
1

I have a setup with two 711G-5hnd boards connected to a 450G. The 711’s are powered through Mikrotik Gigabit POE’s with FTP cables of about 2 meters long.
Everything is grounded, even the 450G case.
Yet, when the storms approaches, the two ports from 450g where the 711’s are connected go down and then back up but in some blocked state as they don’t pass traffic. I have to manually set them to down and up to revive them.
If I uncheck Autonegotiation and leave only 100 Mbps full the ports stop flapping but the performance gets horrible.
I have no ideea what to try next except than changing RB450G with some cheap gigabit tp-link switch. Anyone with this kind of issues around here?

Thanks!

2

Try disabling Auto negotiation on both ends not just on 450G, also the speed and duplex should be the same on both ends. see if that makes any difference

3

Thanks for the hint. 100 Mbps without autonegotiation on both sides solves for a while this issue.