3.1.6 Virtual I/O Server virtualization configuration

The Virtual I/O Server is an appliance that provides virtual storage and shared Ethernet capability to client logical partitions on a POWER5 system. It allows a physical adapter with attached disks on the Virtual I/O Server partition to be shared by one or more partitions, thus enabling clients to consolidate and potentially minimizing the number of physical adapters.

The Virtual I/O Server is the link between the virtual world and the real world. It can be seen as an AIX-based appliance, and it is supported on POWER5 servers only. The Virtual I/O Server runs in a special partition which cannot be used for execution of application code.

It mainly provides two functions:

Server component for Virtual SCSI devices (VSCI target)

Support of shared Ethernet adapters for Virtual Ethernet

Using the Virtual I/O Server facilitates the following functions:

  • Sharing physical resources between partitions on the system
  • Creating partitions without requiring additional physical I/O resources
  • Creating more partitions than there are I/O slots or physical devices available with the ability for partitions to have dedicated I/O, virtual I/O, or both
  • Maximizing physical resource use on the system