Scenario: Create a virtual Ethernet for interpartition communications

You are the system administrator for a small company. You use a server that is divided into four logical partitions. You need to allow communication between all four logical partitions. You want to avoid purchasing excess Ethernet cards and cables because money and space is limited in your IT department.

Situation

You are the system administrator for a small company. You use a server that is divided into four logical partitions. You need to allow high-speed communication between all four logical partitions and you need to extend that communication to an external LAN. Your hardware has a limited number of card slots available for LAN cards. Therefore, you must find a solution that does not require additional LAN cards.

Objectives

As the system administrator for this company, you have the following objectives:

  • To create a virtual Ethernet network to allow communications between logical partitions.
  • To enable proxy ARP to connect the virtual Ethernet network to an external LAN.
  • To configure the necessary lines, interfaces and routes.

Details

This figure shows a virtual Ethernet that enables communication among four logical partitions and uses proxy ARP to allow the data to flow between the virtual Ethernet and the external LAN.


This illustrates four partitions participating in a virtual Ethernet network. Proxy ARP allows the interpartition network traffic to flow to the Internet.
  • Four logical partitions have been created on the iSeries™ server.
  • Each partition runs on i5/OS™ Version 5 Release 3.
  • A virtual TCP/IP interface is configured on each partition using these IP addresses:
    • Partition A has the IP address 10.1.1.73.
    • Partition B has the IP address 10.1.1.74.
    • Partition C has the IP address 10.1.1.75.
    • Partition D has the IP address 10.1.1.76.
  • An external proxy ARP interface is configured on Partition A using the IP address 10.1.1.15.

Prerequisites and assumptions

Setup requirements include:
  • i5/OS Version 5 Release 3 or later installed on the primary logical partition
  • IBM® 270 and 8xx model servers
  • Four logical partitions (LPAR) on the server. The primary logical partition must have i5/OS Version 5 Release 3, or later, installed. The other logical partitions can have i5/OS V5R3 or Linux® installed.

    In this scenario, all of the logical partitions are using i5/OS.

Configuration Steps

Complete these configuration tasks:

  1. Enable the logical partitions to participate in a virtual Ethernet
  2. Create the Ethernet line descriptions
  3. Turn on IP datagram forwarding
  4. Create the interface to enable proxy ARP
  5. Create the virtual Ethernet interface on partition A
  6. Create the virtual Ethernet interface on partition B
  7. Create the virtual Ethernet interface on partition C
  8. Create the virtual Ethernet interface on partition D
  9. Create the routes
  10. Verify network communications
Parent topic: Network scenarios
Related reference
Logical partitions