vsphere-esxi-vcenter-server-55-storage-guide

vSphere StorageRequirements for Using NPIVIf you plan to enable NPIV on your virtual machines, you should be aware of certain requirements.The following requirements exist:• NPIV can be used only for virtual machines with RDM disks. Virtual machines with regular virtualdisks use the WWNs of the host’s physical HBAs.• HBAs on your host must support NPIV.For information, see the vSphere Compatibility Guide and refer to you vendor documentation.• Use HBAs of the same type, either all QLogic or all Emulex. VMware does not supportheterogeneous HBAs on the same host accessing the same LUNs.• If a host uses multiple physical HBAs as paths to the storage, zone all physical paths to the virtualmachine. This is required to support multipathing even though only one path at a time will beactive.• Make sure that physical HBAs on the host have access to all LUNs that are to be accessed by NPIVenabledvirtual machines running on that host.• The switches in the fabric must be NPIV-aware.• When configuring a LUN for NPIV access at the storage level, make sure that the NPIV LUN numberand NPIV target ID match the physical LUN and Target ID.NPIV Capabilities and LimitationsLearn about specific capabilities and limitations of the use of NPIV with ESXi.ESXi with NPIV supports the following items:• NPIV supports vMotion. When you use vMotion to migrate a virtual machine it retains the assignedWWN.If you migrate an NPIV-enabled virtual machine to a host that does not support NPIV, VMkernelreverts to using a physical HBA to route the I/O.• If your FC SAN environment supports concurrent I/O on the disks from an active-active array, theconcurrent I/O to two different NPIV ports is also supported.When you use ESXi with NPIV, the following limitations apply:• Because the NPIV technology is an extension to the FC protocol, it requires an FC switch and does notwork on the direct attached FC disks.• When you clone a virtual machine or template with a WWN assigned to it, the clones do not retain theWWN.• NPIV does not support Storage vMotion.• Disabling and then re-enabling the NPIV capability on an FC switch while virtual machines are runningcan cause an FC link to fail and I/O to stop.Assign WWNs to Virtual MachinesAssign WWN settings to virtual machine with an RDM disk.You can create from 1 to 16 WWN pairs, which can be mapped to the first 1 to 16 physical FC HBAs on thehost.42 VMware, Inc.