On the floor of the Intel Developer Forum last week, I hooked up with SAN HBA vendors Emulex and QLogic to see how they were progressing with the new N-Port ID Virtualization specification.
N-Port ID Virtualization, or NPIV, is a developing specification designed to make it easier to manage virtual servers on a SAN (storage area network).
In Fibre Channel SAN environments, each storage host bus adapter port has a unique WWN (World Wide Name) associated with it that SAN management tools use to monitor and direct storage resources.
In standard server and storage environments, the WWN is useful for identifying storage resources and quickly locating problems.
In the world of server virtualization, however, multiple server images reside on a single physical server, sharing the same HBA and WWN to access storage resources.
This is a nightmare from a management point of view. For example, say a virtual server on a SAN started writing corrupted data to a storage array. When tracking the path back using a SAN management tool, you would be able to trace the fault only as far as the host server—you wouldnt know which virtual instance on the host server was actually causing the problem.
With NPIV, a Fibre Channel HBA and switch can create and manage virtual WWNs that a virtualization manager can discretely assign to virtual servers.
Which leads me back to the IDF floor, where Emulex was showing off a functioning example of how its NPIV technology worked with Xen 3.0 Hypervisor to create and manage virtual storage links between a test SAN and virtual servers.
Interoperability was emphasized in the demo, with the use of Brocade, Cisco Systems and McData switches.
NPIV technology is still a work in progress, but I expect to see it implemented in a number of products within the next few years. And, going forward, I hope vendors expand the specification to include other connectivity options, including iSCSI and SAS (serial-attached SCSI). ´
Senior Analyst Henry Baltazar can be reached at [email protected].