Cisco Certified Support Technician (CCST) NetworkingNetwork AccessMedium
A network technician is configuring an access port on a Cisco switch for a new user's computer. The computer should only be able to access resources within a specific VLAN (VLAN 10) and should not be able to forward frames from other VLANs. Which command set correctly configures this port?
- ASwitch(config-if)# switchport mode access Switch(config-if)# switchport trunk native vlan 10
- BSwitch(config-if)# switchport mode dynamic desirable Switch(config-if)# switchport access vlan 10
- CSwitch(config-if)# switchport mode trunk Switch(config-if)# switchport trunk allowed vlan 10
- DSwitch(config-if)# switchport mode access Switch(config-if)# switchport access vlan 10
Show answer & explanationAnswer & explanation
Correct answer: D. Switch(config-if)# switchport mode access Switch(config-if)# switchport access vlan 10
To configure a switch port for a single end device (like a user's computer) to belong to a specific VLAN, the port must be set to 'access' mode, and then assigned to that VLAN using 'switchport access vlan'. This ensures the port only handles traffic for the specified VLAN.
Why the other options are wrong
- A. Setting a native VLAN on a trunk port is used for untagged traffic on trunks, not for assigning an access port to a VLAN.
- B. Dynamic desirable mode attempts to form a trunk, which is not suitable for an end-user device, and 'switchport access vlan' would still be needed for VLAN assignment.
- C. Trunk mode is used for connections between switches or to routers to carry multiple VLANs, not for end-user devices.
Switch Port Modes (VLANs)
Cisco switches use different port modes (access, trunk, dynamic) to manage how VLAN traffic is handled on a port.
- Access port: Carries traffic for only one VLAN, typically for end devices.
- Trunk port: Carries traffic for multiple VLANs, typically for switch-to-switch or switch-to-router connections.
- VLANs provide logical segmentation of networks.
Memory trick: Access for Users, Trunk for Switches