Important  If you use the P2 interface, the P1 interface is bound to eth0, and the P2 interface is bound to eth1. Keep this in mind when you configure Content Gateway. For example, suppose you are using a transparent proxy deployment, and the P1 interface is connected to a WCCP router. In this case, you must configure Content Gateway to use eth0 for WCCP communications (in Content Gateway manager, see the General tab of the Configure > Networking > WCCP page).

General guideline	The P1 and P2 interfaces can be in the same or different subnets. If they are in the same subnet, P2 is the default gateway (which is bound to eth1). Ensure that outbound packets can reach the Internet. When P1 and P2 are in different subnets, the gateway must be in the same subnet as the appliance interface used to send traffic to the Internet (typically P2). All traffic communicated between Content Gateway and origin servers should go through that interface (P2).   For traffic communicated between Content Gateway and clients, please note: If the clients are in the same subnet as P1, then all traffic communicated between Content Gateway and clients should go through P1. If the clients are not in the same subnet as P1, then client-to-Content Gateway traffic goes through P1, while Content Gateway-to-client traffic goes through P2, regardless of whether an explicit or transparent deployment is used. Note, however, that you can set up static routes to send client traffic (on subnets not attached to P1) back through P1. (inbound traffic)
IP address (P1 or P2 interface)	Required.
Subnet mask	Required.
Default gateway	Required. The gateway must be in the same subnet as the IP address of the interface (P1 or P2) used for communicating with the Internet (outbound traffic). If you use both P1 and P2, they must be located in the same subnet. The default gateway is automatically assigned to P2 (which is bound to eth1). Ensure that outbound packets can reach the Internet.
Primary DNS	Required. IP address of the domain name server.
Secondary DNS	Optional. Serves as a backup in case the primary DNS is unavailable.
Tertiary DNS	Optional. Serves as a backup in case the primary and secondary DNSes are unavailable.