Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) v1.2InfrastructureMedium
A network engineer is configuring a Cisco Catalyst 9300 switch to support multiple VLANs. The requirement is for the switch to act as the default gateway for these VLANs, performing inter-VLAN routing. Which command is used to create a Layer 3 interface for each VLAN on the switch?
- Ainterface gi0/1.10
- Binterface Vlan 10
- Cinterface loopback 0
- Dinterface Port-channel 1
Show answer & explanationAnswer & explanation
Correct answer: B. interface Vlan 10
The 'interface Vlan' command is used to create a Switched Virtual Interface (SVI) on a Layer 3 switch, which acts as the default gateway for a specific VLAN and enables inter-VLAN routing.
Why the other options are wrong
- A. This command creates a subinterface on a physical interface, typically used for Router-on-a-Stick, not for SVIs on a Layer 3 switch.
- C. This command creates a loopback interface, which is a virtual interface used for management and routing protocols, not for inter-VLAN routing.
- D. This command creates a Port-channel interface, used for link aggregation (EtherChannel), not for inter-VLAN routing.
Switched Virtual Interface (SVI)
An SVI is a logical Layer 3 interface on a Layer 3 switch associated with a VLAN, providing a default gateway for that VLAN and enabling inter-VLAN routing.
- Created with 'interface Vlan <VLAN_ID>'.
- Requires a Layer 3 switch.
- Acts as default gateway for VLAN members.
- Enables routing between VLANs.
Memory trick: VLAN interface, the gateway's face, for routing traffic to a new place.