[SOLVED] RB260GS switch and NETWATCH

Main router RB3011 (192.168.1.1) is connected with switch RB260GS (192.168.1.9) by optic cable (I use built in SFP of both devices).

I would like to monitor that RB260GS is working by Netwatch tool from RB3011

But RB3011’s Netwatch shows that switch is always down and ping to 192.168.1.9 gets “Timeout” from Winbox’s terminal
But I can successfully open web interface of RB260GS in browser. And I can ping 192.168.1.9 from my computer.

How to make RB3011’s Netwatch to ping RB260GS? Something in RB260GS’s port mirroring?

Please anyone help. Why main router RB3011 can’t ping RB260GS connected by fibre?
RB3011 is CapsMan for several access points. I can ping RB260GS from terminal (Winbox) of any of those access points.
But I can’t from RB3011.

RB260GS is located far from main office and I need to know when power lost happens on remote end.
Of course, netwatching from any of access points could be a some workaround, but my access points are not powered by UPS. But RB3011 has UPS.
So why RB3011 can’t ping remote RB260GS, but it can ping any device that connected to ports 1-5 of that RB260GS?

Problem is solved. I forgot that I made special setting on my bridge interface for prohibition unknown devices with static addresses to get Internet access from LAN.
This is “reply-only” in ARP settings of interface.
RB260GS has static address too. This is why RB3011 could not ping RB260GS.
The solution is simple:
Winbox IP, ARP table: add new record with IP and MAC of RB260GS.
Now Netwatch tool for RB260GS is working