By default, all the ports are configured as unified ports until gen 2 but FI 6332-16UP model in gen 3 has first 16 unified ports and FC ports require additional one-time disruptive configuration on both Fabric Interconnects. Fabric Interconnect provides unified port configuration manager that can change the Ethernet port mode to the FC port. You need to plan ahead on the total number of FC ports required for your application, otherwise changing the port mode will  require a reboot of Fabric Interconnect in the future. Perform the following steps to configure the FC port for gen 2 FI where gen 3 FI required slider configuration from right to left side for first 16 unified ports with FI 6332-16UP model:

1. Log into UCS Manager.
2. Click on the Equipment tab in the navigation pane.
3. In the Equipment tab, click on Fabric Interconnect A.
4. In the Actions area of the work pane, click on Configure Unified Ports. 
5. Click on Yes on the pop-up warning message to restart the Fabric Interconnect.

6. Configure Fixed Module Ports by dragging the slider (following the Fabric Interconnect screenshot) from the right side to left side depending upon the number of FC ports required.

7. Click on the Next option to configure the remaining expansion modules if they are available on the Fabric Interconnect.
8. Click on Finish to restart the Fabric Interconnect.
9. Click on Yes on the pop-up warning message to restart the Fabric Interconnect:

10. Repeat the aforementioned steps for the secondary Fabric Interconnect.