Web example: Configuring outbound dynamic NAT (non-overlapping addresses)

Network configuration

As shown in Figure-1, the company has public addresses 200.2.2.1/24 to 200.2.2.3/24. Configure NO-PAT translation to enable hosts in the internal network to access the server on the Internet.

Figure-1 Network diagram

Software versions used

This configuration example was created and verified on E9900 of the F5000-AI-55-G device.

Restrictions and guidelines

Do not configure both the NAT translation methods and a global NAT policy.

Procedure

  1. Assign IP addresses to interfaces and add the interfaces to security zones.

    # On the top navigation bar, click Network.

    # From the navigation pane, select Interface Configuration > Interfaces.

    # Click the Edit icon for GE 1/0/1.

    # In the dialog box that opens, configure the interface:

    1. Select the Untrust security zone.

    2. On the IPv4 Address tab, enter the IP address and mask of the interface. In this example, enter 200.2.2.254/24.

    3. Click OK.

    # Add GE 1/0/2 to the Trust security zone and set its IP address to 172.16.100.254/24 in the same way you configure GE 1/0/1.

  2. Configure settings for routing.

    This example configures a static route. If dynamic routes are required, configure a dynamic routing protocol.

    # On the top navigation bar, click Network.

    # From the navigation pane, select Routing > Static Routing.

    # On the IPv4 Static Routing tab, click Create.

    # In the dialog box that opens, configure a static route to permit packets from the internal hosts to the external server:

    1. Specify the IP address of the server as the destination IP. In this example, the address is 100.100.100.100.

    2. Enter the mask length. In this example, enter 24.

    3. Specify the next-hop address as 200.2.2.253.

    4. Click Apply.

  3. Configure a security policy.

    # On the top navigation bar, click Policies.

    # From the navigation pane, select Security Policies > Security Policies.

    # Click Create and click Create a policy.

    # In the dialog box that opens, configure policy parameters as follows:

    1. Enter a policy name. In this example, the name is Secpolicy.

    2. Select the source zone. In this example, the source zone is Trust.

    3. Select the destination zone. In this example, the destination zone is Untrust.

    4. Select IPv4 as the type.

    5. Select Permit as the action.

    6. Specify the IP addresses of the hosts as the source IPv4 addresses. In this example, the addresses are 172.16.100.1, 172.16.100.2, 172.16.100.3.

    7. Specify the IP address of the server as the destination IPv4. In this example, the address is 100.100.100.100.

    8. Click Apply.

  4. Configure a NAT address group.

    # On the top navigation bar, click Objects.

    # From the navigation pane, select Object Groups > NAT Address Groups.

    # Click Create.

    # Create a NAT address group, as shown in Figure-2.

    Figure-2 Creating a NAT address group

    # Click Apply.

  5. Configure an outbound dynamic NAT rule.

    # On the top navigation bar, click Policies.

    # From the navigation pane, select Interface NAT > IPv4.

    # On the Out Dynamic NAT (Object Group-Based) tab, click Create.

    # Create an outbound dynamic NAT rule, as shown in Figure-3.

    Figure-3 Creating an outbound dynamic NAT rule

    # Click Apply.

Verifying the configuration

  1. Verify that the host can successfully ping the server on the external network.

    C:\Users\abc>ping 100.100.100.100

    Pinging host.com [100.100.100.100] with 32 bytes of data:

    Reply from 100.100.100.100: bytes=32 time<1ms TTL=253

    Reply from 100.100.100.100: bytes=32 time<1ms TTL=253

    Reply from 100.100.100.100: bytes=32 time<1ms TTL=253

    Reply from 100.100.100.100: bytes=32 time<1ms TTL=253

    Ping statistics for 100.100.100.100:

    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

    Approximate round trip times in milli-seconds:

    Minimum = 0ms, Maximum = 0ms, Average = 0ms

  2. Verify that a NAT session is generated when the host accesses the server.

    # On the top navigation bar, click Monitor.

    # From the navigation pane, select Sessions.

    Figure-4 Session list