Step 4: Creating the interface to enable proxy ARP

You need to create an external interface to enable proxy ARP.

To create the TCP/IP interface to enable proxy ARP, complete these steps:

  1. Obtain a contiguous block of IP addresses that are routable by your network.

    Because you have two partitions in this virtual Ethernet, you need a block of four addresses. The fourth segment of the first IP address in the block must be divisible by four. The first and last IP addresses of this block are the subnet and broadcast IP addresses are unusable. The second and third IP address can be used for the TCP/IP interfaces for the virtual Ethernet on partition A and partition B. For this procedure, the IP address block is 10.1.1.72 through 10.1.1.75 with a subnet mask of 255.255.255.252.

    You also need a single IP address for your external TCP/IP address. This IP address does not have to belong to your block of contiguous addresses, but it must be within the same original subnet mask of 255.255.255.0. In this procedure, the external IP address is 10.1.1.15.

  2. Create an IBM® i TCP/IP interface for partition B. This interface is known as the external, proxy ARP IP interface. To create the interface, follow these steps:
    1. On the command line on partition B, type CFGTCP (Configure TCP/IP command), and then press Enter to see the Configure TCP/IP window.
    2. Select Option 1 (Work with TCP/IP Interfaces), and then press Enter.
    3. Select Option 1 (Add), and then press Enter to see the Add TCP/IP Interface (ADDTCPIFC) window.
    4. At the Internet address prompt, type 10.1.1.15.
    5. At the Line description prompt, type the name of your line description, such as ETHLINE.
    6. At the Subnet mask prompt, type 255.255.255.0.
  3. Start the interface. On the Work with TCP/IP Interfaces window, select Option 9 (Start) by the interface.