You only need to configure NAT if the firewall
has an external interface used for connecting to networks outside
of your data center. While NAT is not required, you can use this
procedure to translate private IP addressing in your data center
to public IP addressing outside. Begin setting up NAT by configuring
address translation for traffic entering server inside an EPG in
your data center. Then configure a NAT policy that translates the
source address of outbound traffic from any EPG to the external
interface IP address.