Whilst revising for the VCP4 Beta Exam and also replying to a thread on the VMTN Forum, I’ve come across a couple of instances where there is a lack of “using NPIV in VMware ESX 4” information. The only good post I can find is Jason Boche‘s post; N_Port ID Virtualization (NPIV) and VMware Virtual Infrastructure, but his post is written and tested using ESX3.5. So I have decided to find out as much information as I can and post it here.

Definition: NPIV stands for N_Port (Node Port) ID Virtualization

What does NPIV do? NPIV is a useful Fibre Channel feature which allows a physical HBA (Host BUS Adapter) to have multiple Node Ports. Normally, a physical HBA would have only 1 N_Port ID. The use of NPIV enables you to have multiple unique N_Port ID’s per physical HBA. NPIV can be used by ESX4 to allow more Fibre Channel connections than the maximum physical allowance which is currently 8 HBA’s per Host or 16 HBA Ports per Host.   See the image above for a graphical representation of NPIV.

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