Layer 3 Interfaces
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Focus

Layer 3 Interfaces

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End-of-Life (EoL)

Layer 3 Interfaces

In a Layer 3 deployment, the firewall routes traffic between multiple ports. Before you can Configure Layer 3 Interfaces, you must configure the Virtual Routers that you want the firewall to use to route the traffic for each Layer 3 interface.
If you’re using security group tags (SGTs) in a Cisco TrustSec network, it’s a best practice to deploy inline firewalls in either Layer 2 or virtual wire mode. However, if you need to use a Layer 3 firewall in a Cisco TrustSec network, you should deploy the Layer 3 firewall between two SGT exchange protocol (SXP) peers, and configure the firewall to allow traffic between the SXP peers.
The following topics describe how to configure Layer 3 interfaces, and how to use Neighbor Discovery Protocol (NDP) to provision IPv6 hosts and view the IPv6 addresses of devices on the link local network to quickly locate devices.