Specifications

Chapter 3. Virtualization 93
Draft Document for Review May 12, 2014 12:46 pm 5102ch03.fm
smaller systems. The virtual SCSI server (target) adapter is responsible for executing any
SCSI commands that it receives. It is owned by the Virtual I/O Server partition. The virtual
SCSI client adapter allows a client partition to access physical SCSI and SAN attached
devices and LUNs that are assigned to the client partition. The provisioning of virtual disk
resources is provided by the Virtual I/O Server.
Physical disks that are presented to the Virtual/O Server can be exported and assigned to a
client partition in various ways:
򐂰 The entire disk is presented to the client partition.
򐂰 The disk is divided into several logical volumes, which can be presented to a single client
or multiple clients.
򐂰 As of Virtual I/O Server 1.5, files can be created on these disks, and file-backed storage
devices can be created.
The logical volumes or files can be assigned to separate partitions. Therefore, virtual SCSI
enables sharing of adapters and disk devices.
For more information about specific storage devices that are supported for Virtual I/O Server,
see the following web page:
http://www14.software.ibm.com/webapp/set2/sas/f/vios/documentation/datasheet.html
N_Port ID Virtualization
N_Port ID Virtualization (NPIV) is a technology that allows multiple logical partitions to access
independent physical storage through the same physical Fibre Channel adapter. This adapter
is attached to a Virtual I/O Server partition that acts only as a pass-through, managing the
data transfer through the POWER Hypervisor.
Each partition that uses NPIV is identified by a pair of unique worldwide port names, enabling
you to connect each partition to independent physical storage on a SAN. Unlike virtual SCSI,
only the client partitions see the disk.
For more information and requirements for NPIV, see the following resources:
򐂰 PowerVM Migration from Physical to Virtual Storage, SG24-7825
򐂰 IBM PowerVM Virtualization Managing and Monitoring, SG24-7590
Virtual I/O Server functions
The Virtual I/O Server has many features, including monitoring solutions:
򐂰 Support for Live Partition Mobility starting on POWER6 processor-based systems with the
PowerVM Enterprise Edition. For more information about Live Partition Mobility, see 3.4.5,
“PowerVM Live Partition Mobility” on page 94.
򐂰 Support for virtual SCSI devices backed by a file, which are then accessed as standard
SCSI-compliant LUNs.
򐂰 Support for virtual Fibre Channel devices that are used with the NPIV feature.
򐂰 Virtual I/O Server Expansion Pack with additional security functions such as Kerberos
(Network Authentication Service for users and client and server applications), Simple
Network Management Protocol (SNMP) v3, and Lightweight Directory Access Protocol
(LDAP) client functionality.
򐂰 System Planning Tool (SPT) and Workload Estimator, which are designed to ease the
deployment of a virtualized infrastructure. For more information about the System
Planning Tool, see 3.5, “System Planning Tool” on page 101.