The Lazy Networker

Basic VLAN and interface configuration on a Cisco switch involves creating VLANs, assigning ports, and managing trunk/access modes. The fundamental commands and workflow are outlined below.

Create a VLAN

To create VLANs (e.g., VLAN 10 and VLAN 20):

Switch> enable
Switch# configure terminal
Switch(config)# vlan 10
Switch(config-vlan)# exit
Switch(config)# vlan 20
Switch(config-vlan)# exit

This creates VLANs 10 and 20 if they do not already exist.

Assign Name to VLAN (Optional)

To name a VLAN:

Switch(config)# vlan 10
Switch(config-vlan)# name Sales
Switch(config-vlan)# exit

Naming helps with identification, especially in large environments.

Assign Switch Ports to VLAN

To assign a port to VLAN 10:

Switch(config)# interface fastethernet 0/1
Switch(config-if)# switchport mode access
Switch(config-if)# switchport access vlan 10
Switch(config-if)# exit

To assign another port to VLAN 20:

Switch(config)# interface fastethernet 0/2
Switch(config-if)# switchport mode access
Switch(config-if)# switchport access vlan 20
Switch(config-if)# exit

Assigning ports assigns their traffic to the selected VLAN.

Assign Multiple Ports (Interface Range)

To assign several interfaces at once:

Switch(config)# interface range fastethernet 0/3 - 0/8
Switch(config-if-range)# switchport mode access
Switch(config-if-range)# switchport access vlan 10
Switch(config-if-range)# exit

This saves time on large switches.

Configure Trunk Ports

For inter-switch links (carry multiple VLANs):

Switch(config)# interface gigabitEthernet 0/1
Switch(config-if)# switchport mode trunk
Switch(config-if)# exit

Trunk ports are required for connecting switches together and passing multiple VLANs.

Common Show Commands

• Check VLANs:

Switch# show vlan

• Check interface status:

Switch# show interfaces status

• Check port VLAN assignment:

Switch# show running-config

These commands help verify configuration and troubleshoot issues.

This basic command set prepares a Cisco switch for segmented, secure communication in most enterprise or learning lab environments