I have replaced old Cisco 1900 switches with 3850's in my plant process areas.
Added Fiber links between 3850's for increased performance. I can't get data transfer through the fiber uplinks.
I have assigned some of the LAN ports to the different VLANS and they are communicating correctly. The Gib Fiber ports when assigned to the VLAN do not pass data.
As a "Band-Aid" I installed Fiber media convertors to connect the fiber backbone to the VLANs. Data does pass through the convertors to the VLAN ports.
Not sure what I'm missing as why the fiber ports aren't passing data as the LAN ports are.
Gone through several Cisco manuals and checked multiple options with no success.
My process is operational so I am now limited in my access to the switches until the next shutdown.
Any suggestions would be appreciated.