For example, put F0/3 into VLAN 2 and enter global configuration mode:

Interface f0/3 enters interface configuration mode.

Switch port mode access configures the interface as an access interface.

Switch port access vlan 2 configuration interface VLAN ID

Conversely, if you want to delete F0/3 from VLAN 2, you can use the no command to delete the above configuration, and F0/3 will return to the native VLAN of the switch. The command is:

No switch ports access vlan 2.

2. Default interface ... I don't know what command you are talking about, but I don't think I have seen it before.

3.F0/3, the first number of the two numbers, 0, stands for [equipment slot number], and the second number, 3, stands for [board port number]. Because some large-scale network devices with high integration have multiple card slots.

In addition, some devices can insert multiple daughter cards into a slot. At this point, for example, F 1/2/3 will appear in the port name. At this time 1 stands for slot, 2 stands for daughter card and 3 stands for port.