RBS50 always offine

What is the Mfr and model# of the ISP modem the NG router is connected too?
Is the Orbi system operating in Router or AP mode?

How are the Satellites connected? Wireless or wired? 

What is the Mfr and model# of the ethernet switch if one is in the configuration.

What is the size of your home? Sq Ft?
What is the distance between the router and satellite(s)? 30 feet is recommended in between them to begin with depending upon building materials.

What channels are you using? Auto? Try setting manual channel 1, 6 or 11 on 2.4Ghz and any unused channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?
What WPA security modes are you using?

Try enabling Beamforming and MIMO.

Try disabling the following and see:
Daisy Chain, Fast Roaming, IPv6 and Set 20/40Mhz Coexistence to 40Mhz only. Save settings and reboot the router and satellite(s).

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Swap wrote:
My satellite RBS50 always offline, why is that? No matter you do restart or sync it again n again . It has latest firmware

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