AiROnE is right !
It works fine with 9898 UDP open in Syno Firewall !
Thanks a lot !

EDIT : I speek to fast... All the devices are correctly recognized.
I don't see the motion sensor.
Does somebody have an idea ?

Thanks for your answer.
If it's working for you with the same configuration i don't know where can my problem come from?

Yes there are on the same subnet.
The synology is 192.168.1.19
The Gateway is 192.168.1.2

Thanks to your analyse I realize that the Ip that Domoticz gives for the gateway corresponds to the ip of the Synology.
How to fix this?

Version: Domoticz Stable V3.8153 for DSM 6.1 Platform: Synology DS413J Hi, I have some problems about running the Xiaomi Gateway on Domoticz installed on my Synology DS413J. Indeed, the Gateway does not appear in the list of devices. I followed this tutorial: https://www.domoticz.com/wiki/Xiaomi ...