VLAN Configuration #
VLAN Setup #
Create VLAN #
Switch# configure terminal
Switch(config)# vlan <vlan_num>
Switch(config-vlan)# name <vlan_name> (optional)
Assign Port to VLAN #
The interface is in a specific vlan, switch would forwards network traffic from those the same vlan to this interface.
Switch(config)# interface <interface>
Switch(config-if)# switchport mode access
Switch(config-if)# switchport access vlan <vlan_num>
Available VLAN Ranges #
| VLANs | Range | Usage |
|---|---|---|
| 0, 4095 | Reserved | For system use only. You cannot see or use these VLANs. |
| 1 | Normal | Cisco default. You can use this VLAN but you cannot delete it. Cisco will use this VLAN to send Control Plane Traffic. |
| 2-1001 | Normal | For Ethernet VLANs. You can create, use, and delete these VLANs. |
| 1002-1005 | Normal | You cannot delete VLANs 1002-1005. |
| 1006-4094 | Extended | For Ethernet VLANs only. |
Trunk Configuration #
Configure Trunk Link #
The interface would allowes some vlans, and switch would forwards network traffic from those allowed vlans.
Switch(config)# interface <interface>
Switch(config-if)# switchport trunk encapsulation {isl | dot1q | negotiate}
Switch(config-if)# switchport mode trunk
Switch(config-if)# switchport trunk allowed vlan {<vlan_list> | except <vlan_list> | all}
<vlan_list>should be in the format of<vlan_num>,<vlan_num>,<vlan_num>.
Modify Existing Trunk Link #
Switch(config-if)# switchport trunk allowed vlan {add | remove} <vlan_list>
Configure Native VLAN #
When a trunk interface transmit packet with its native VLAN, it will send the packet untagged.
Switch(config)# interface <interface>
Switch(config-if)# switchport trunk encapsulation dot1q
Switch(config-if)# switchport trunk native vlan <vlan_num>
L3 Switch Configuration #
Create VLAN on L3 Switch #
Switch# configure terminal
Switch(config)# vlan <vlan_num>
Switch(config-vlan)# name <vlan_name> (optional)
Configure VLAN Interface #
Switch(config)# interface vlan <vlan_num>
Switch(config-if)# ip address <ip_address> <subnet_mask>
Set the Default Gateway #
Switch(config-if)# ip default-gateway <ip_address>
Enable Routing on L3 Switch #
Switch(config)# ip routing
Configure Uplink Interface #
Switch(config)# interface <interface>
Switch(config-if)# no switchport
Switch(config-if)# ip address <ip_address> <subnet_mask>
Verify VLAN Configuration #
Switch# show vlan brief
Switch# show vlan id <vlan_num>
Switch# show interface vlan <vlan_num>