Palo Alto Networks Certified Network Security Engineer (PCNSE)Core ConceptsEasy
A network security administrator is configuring a new Palo Alto Networks firewall and wants to ensure that all traffic destined for the internet is routed through a specific external gateway. Which type of interface configuration would best support this requirement for the external-facing port?
- AVirtual Wire
- BLayer 2
- CLayer 3
- DTap
Show answer & explanationAnswer & explanation
Correct answer: C. Layer 3
A Layer 3 interface is essential for routing traffic between different IP subnets and for connecting to external networks like the internet via a default gateway. This configuration allows the firewall to participate in routing decisions.
Why the other options are wrong
- A. Virtual Wire interfaces are used for transparently inserting a firewall into an existing network segment without changing the network topology.
- B. Layer 2 interfaces are primarily for switching within the same subnet and do not handle routing to external networks directly.
- D. Tap interfaces are used for passive monitoring of network traffic and do not forward packets.
Layer 3 Interface
A Layer 3 interface on a Palo Alto Networks firewall is configured with an IP address and acts as a router port, enabling routing between different IP subnets and connecting to external networks.
- Has an IP address and subnet mask.
- Participates in routing decisions.
- Can be configured with virtual routers and routing protocols.
Memory trick: Route to the Net? Need Layer 3, no sweat!