Figure 11 Direct attach and Fabric attach Fibre Channel networks

Fabric-attached HP storage devices

HP 3PAR Storage System

 

 

 

 

 

 

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HP BladeSystem c7000 Enclosure

15.4.1.2 Fabric attach Fibre Channel networks

SAN infrastructures typically use a Fibre Channel switching solution involving several SAN switches that implement NPIV (N-Port ID Virtualization) technology. NPIV uses N-ports and F-ports to build a Fibre Channel SAN fabric. NPIV enables multiple N_Ports to connect to a switch through a single F_Port, so that a virtual server can share a single physical port with other servers, but access only its associated storage on the SAN.

When you configure a Fabric attach Fibre Channel network, the port you choose for the uplink from the enclosure interconnect to the storage SAN must support NPIV (N_Port ID Virtualization).

15.4.1.3 Direct attach Fibre Channel networks

The Direct attach Fibre Channel solution, also called the Flat SAN solution, eliminates the need for a connection from the enclosure interconnects to a Fibre Channel SAN switch. This means you can connect the enclosure interconnects directly to the storage system. The port you choose for the uplink from the enclosure interconnect to the storage system must support NPIV.

Servers connecting to a Direct attach Fibre Channel network have access to all devices connected on the uplink ports defined for that network. If there is more than one connection from a FlexFabric module to the storage system, each server can access as many paths to the storage LUN (logical unit number) as there are connections to the storage system.

For Direct attach Fibre Channel networks, the enclosure interconnect does not distribute server logins evenly across uplink ports. Server login-balancing and login-distribution do not apply to Fibre Channel networks.

118 Managing networks and network resources