Configuring a virtual Ethernet adapter

You can configure a virtual Ethernet adapter dynamically for a running logical partition by using the Hardware Management Console (HMC). Doing so will connect the logical partition to a virtual LAN (VLAN).

Before you begin

You can dynamically configure a virtual Ethernet adapter for a Linux® logical partition only if the following conditions are met:
  • A Linux distribution that supports dynamic partitioning is installed on the Linux logical partition. Distributions that support dynamic partitioning include SUSE Linux Enterprise Server 9 and later versions.
  • The DynamicRM tool package is installed on the Linux logical partition. To download the DynamicRM tool package, see the Service and productivity tools for Linux on POWER® systems website.
If you plan to configure an Ethernet adapter for a logical partition that uses shared memory (hereafter referred to as a shared memory partition), you might need to adjust the amount of I/O entitled memory assigned to the shared memory partition before you configure the adapter:
  • If the I/O entitled memory mode of the shared memory partition is set to the auto mode, you do not need to take action. When you configure the new Ethernet adapter, the HMC automatically increases the I/O entitled memory of the shared memory partition to accommodate the new adapter.
  • If the I/O entitled memory mode of the shared memory partition is set to the manual mode, you must increase the I/O entitled memory that is assigned to the shared memory partition to accommodate the new adapter. For instructions, see Adding and removing I/O entitled memory dynamically to and from a shared memory partition.

About this task

For more information about managing virtual network connections on a logical partition when the HMC is at version 8.7.0, or later, see Managing virtual network connections.

Note: In the AIX® operating system, the receive buffers pools of the Virtual Ethernet increases in size and shrinks. When the load increases, the receive buffers pools increases by several buffers. The buffer pools can increase in size until the maximum value is reached (defined by the buf_mode attribute). When the load decreases, the receive buffers pools shrink to the minimum value (defined by the buf_mode attribute). The buf_mode attribute has the following possible values:
  • min - Allocate the minimum buffer values. Increase as required and shrink back to min values.
  • max - Allocate the maximum buffer values. Shrink is disabled. Fail the device open operation if the maximum values cannot be allocated.
  • max_min - Attempt the maximum mode. If the maximum values cannot be allocated, then fall back to minimum mode.
You can run the entstat command on the Virtual Ethernet adapter to display the number of buffers that are allocated by the device.

What to do next

After you have finished, access any existing partition profiles for the logical partition and add the virtual Ethernet adapters to those partition profiles. The virtual Ethernet adapter is lost if you shut down the logical partition and activate that logical partition using a partition profile that does not have the virtual Ethernet adapter in it.