@DIT Hi,My switch is TL-SG2210P, I can use this function normally in standalone mode. many-to-one means only one port can be used as mirroing port at the same time. According to your error message, I suspect that the problem is caused by your wrong settings.

@Yannie  Hi Yanni, Thanks for the response. Just to clarify, you can use your port forwarding setup in standalone mode, but not when the swtich is controlled by the Omada controller?

Many-to-One port mirroring means many ports on the switch can be mirrored to one port port on the switch. (You described One-to-Many port mirroring where one port on the switch is mirrored to many ports on the same switch.

I need Many-to-One port mirroring. Traffic from many ports (connecting many phones in this case) mirrored to ONE port (where call recording software on a server lives).

DIT