I have a setup of Cat 9k Meraki all having this UDLD issue on copper ports, all connecting to C9300-48UXM and C9300-48UXM uplink to MX. 1 C9300-48UXM 2 C9300-48U 2 C9300-48P   4 of the setup are now running CS 16.9 and seems stable for the past week after i did the firmware upgrade but one unit of C9300-48P is still refusing to function properly, may need to directly link it to the MX to allow proper upgrade of the firmware. ... View more

Ah, one thing I forgot to mention is that as far as I know you need to add the switches manually with the serial number or purchase order number, they are not added automatically. ... View more