NPIV tackles the problem of how multiple virtual servers get access to the FC SAN. Usually the SAN wants one port ID for each server. It uses the port ID as the basis for masking and zoning. However, "virtual servers share the physical HBA and get a virtual port ID," explains Clodoaldo Barrera, distinguished engineer and chief technical strategist for IBM's System Storage Group. NPIV defines how multiple virtual servers can share a single physical port ID.
For storage managers, NPIV will be almost transparent. "To get the benefit of NPIV, it must be supported in the HBA and the switch," says Scott McIntyre, VP of software and customer marketing at Emulex Corp. HBA and switch vendors have started building NPIV into their products. Companies will get NPIV as they upgrade their HBAs and switches.
NPIV also needs to happen in the virtualization software. Microsoft Corp.'s Virtual Server began supporting NPIV in 2007. VMware is expected to support NPIV in 2008. IBM supports a version of NPIV for its System z and is working it into its blade servers, which presents a somewhat more complicated technical challenge. But again, this is something vendors, not corporate storage managers, are wrestling with.This isn't to say storage managers can ignore NPIV. To take advantage of NPIV, they'll have to check the latest hardware, firmware and server operating system versions for NPIV support. Once deployed, storage administrators will need to be aware of NPIV because it may impact how they set up the fabric, handle zoning and masking, and manage quality of service.
This material originally appeared in Storage magazine.