Configure Networking for Protected Traffic Between the Site-To-Site Peers

After completing the configuring of the Site-To-Site connection, make sure that you perform the following configuration for VPN to function on all targeted devices.

Procedure


Step 1

Configure AC policies:

Configure AC policies for permitting bidirectional traffic between the protected networks behind both peers. These policies help the packets to traverse to the intended destination without being dropped.

Note

You must create AC policies for incoming and outgoing traffic on both peers.

  1. In the Cisco Defense Orchestrator navigation bar at the left, click Policies and select the option that you want.

  2. Create policies for incoming and outgoing traffic on both peers. For more information on AC policy creation, see Configure the FDM Access Control Policy.

    The following example shows steps for creating AC policies on both peers.

    Consider two FDM-managed devices 'FTD_BGL_972' and 'FTD_BGL_973' with Site-To-Site VPN connection between two protected networks 'boulder-network' and 'sanjose-network' respectively.

    Creating the AC policy for permitting incoming traffic:

    The policy 'Permit_incoming_VPN_traffic_from_973' is created on the 'FTD_BGL_972' device for allowing incoming traffic from the peer ('FTD_BGL_973').

    • Source Zone: Set the zone of the peer device from which the network traffic originates. In this example, the traffic is originating from FTD_BGL_973 and reaching FTD_BGL_972.

    • Source Network: Set the protected network of the peer device from which the network traffic originates. In this example, traffic is originating from 'sanjose-network' which is the protected network behind the peer device (FTD_BGL_973).

    • Destination Network: Set the protected network of the device on which the network traffic arrives. In this example, traffic is arriving at 'boulder-network' which is the protected network behind the peer device (FTD_BGL_972). Note: The remaining fields can have the default value ("Any").

    • Set Action to Allow for allowing the traffic subject to the intrusion and other inspection settings in the policy.

    Creating the AC policy for permitting outgoing traffic:

    The policy 'Permit_outgoing_VPN_traffic_to_973' is created on the 'FTD_BGL_972' device for permitting outgoing traffic to the peer ('FTD_BGL_973').

    • Source Network: Set the protected network of the peer device from which the network traffic originates. In this example, traffic is originating from 'boulder-network' which is the protected network behind the peer device (FTD_BGL_972).

    • Destination Zone: Set the zone of the peer device on which the network traffic arrives. In this example, the traffic is arriving from FTD_BGL_972 and reaching FTD_BGL_973.

    • Destination Network: Set the protected network of the peer on which the network traffic arrives. In this example, traffic is arriving on 'sanjose-network' which is the protected network behind the peer device (FTD_BGL_972). Note: The remaining fields can have the default value ("Any").

    • Set Action to Allow for allowing the traffic subject to the intrusion and other inspection settings in the policy.

After creating AC policies on one device, you must create similar policies on its peer.

Step 2

If NAT is configured on either of the peer devices, you need to configure the NAT exempt rules manually. See Exempting Site-to-Site VPN Traffic from NAT.

Step 3

Configure routing for receiving the return VPN traffic on each peer. For more information, see Configure Routing.

  1. Gateway-Select the network object that identifies the IP address for the gateway to the destination network. Traffic is sent to this address.

  2. Interface-Select the interface through which you want to send traffic. In this example, the traffic is sent through 'outside' interface.

  3. Destination Networks-Select one or network objects, that identify the destination network. In this example, the destination is 'sanjose-network' which is behind peer (FTD_BGL_973).

After configuring routing settings on one device, you must configure similar settings on its peer.