フリー問題

問題文

Why would an engineer configure a loopback interface on a firewall that already has several physical Layer 3 interfaces?

選択肢

1. To provide a place to terminate GRE and IPSec tunnels, because tunnel interfaces cannot be created unless a loopback interface exists on the firewall first.
2. To give the firewall a stable address that stays reachable as long as any path to the firewall is up, so that services bound to it survive a physical link failure.
3. To let the firewall participate in a VLAN without consuming a physical port, which is the way an interface is added to a VLAN object.
4. To add a logical path through which the dataplane can send packets in parallel with the physical ports, increasing the forwarding capacity of the firewall.