Hello, you can follow these steps:
In the Main Topology of the NMS, right-click the desired NE and choose NE Explorer from the shortcut menu.
In the NE Explorer, select the desired board and choose from the Function Tree.
Click By Board/Port(Channel). Select Channel from the drop-down list.
On the Basic Attributes tab, double-click the Channel Use Status field and select Used or Unused to set the channel use status of the optical port.
Click Apply.
Thank you!