Emulex has developed a way for several virtual servers to each access private storage resources across a network.

Currently a server can only access its own dedicated part of a storage area network. Virtual servers running in that server all share the same storage.

Emulex' Virtual HBA technology will however mean VMware virtual servers can access their own dedicated storage area network (SAN) resources, while still using the host server's single host bus adapter (HBA). It means sysadmins can now manage the SAN and its access with much more precision and security.

Without this, existing virtual server systems must use shared resources on the SAN. This limits which applications can run in the virtual servers or compromises privacy and security. An ordinary user in one virtual server could access sensitive data accessed by an application in another virtual server.

With the Emulex technology this needn't be allowed to happen. Techniques such as zoning, LUN mapping and masking can now be used at the virtual server level whereas before they could only be used at the physical server level.

Emulex uses N_Port ID Virtualisation or NPIV. This concept is already in use with Brocade SilkWorm 48000 director and IBM's z9 mainframe which uses FICON connectivity. NPIV is an extension of the InterNational Committee for Information Technology Standardisation (INCITS) Fibre Channel standard.Cisco and McDATA also support it. The director or switch maps the virtual HBA ports to physical SAN fabric ports.

Emulex has implemented NPIV in its LightPulse HBAs via firmware and driver upgrades. As virtual servers become more popular the demand for virtual server-specific SAN data areas is expected to rise. It also justifies the use of faster 4Gbit/s Fibre Channel connectivity to servers as each HBA has to handle more traffic.