Virtual I/O Server overview

Learn the concepts of the Virtual I/O Server (VIOS) and its primary components.

The VIOS is part of the PowerVM® Editions hardware feature. The VIOS is a software that is located in a logical partition. This software facilitates the sharing of physical I/O resources between client logical partitions within the server. The VIOS provides virtual Small Computer Serial Interface (SCSI) target, virtual Fibre Channel, Shared Ethernet Adapter, and PowerVM Active Memory Sharing capability to client logical partitions within the system. The VIOS also provides the Suspend/Resume feature to AIX®, IBM® i, and Linux® client logical partitions within the system when you are managing a POWER7®, POWER8®, or POWER9™ processor-based server.
Note: The Suspend/Resume feature of logical partitions is not supported on the POWER9 Power Systems servers. This feature is supported on other models of Power Systems servers, with appropriate levels of the management console, firmware, and PowerVM.
As a result, you can perform the following functions on client logical partitions:
  • Share SCSI devices, Fibre Channel adapters, Ethernet adapters
  • Expand the amount of memory available to logical partitions and suspend and resume logical partition operations by using paging space devices when you are managing a POWER7, POWER8, or POWER9 processor-based server.

A dedicated logical partition is required for the VIOS software solely for its use.

You can use the VIOS to perform the following functions:
  • Sharing of physical resources between logical partitions on the system
  • Creating logical partitions without requiring additional physical I/O resources
  • Creating more logical partitions than there are I/O slots or physical devices available with the ability for logical partitions to have dedicated I/O, virtual I/O, or both
  • Maximizing use of physical resources on the system
  • Helping to reduce the storage area network (SAN) infrastructure