What is NPIV?
NPIV enables a single FC HBA port to register several unique WWNs with the fabric, “each of which can be assigned to an individual virtual machine”.
When virtual machines have WWN assignments, they use them for all RDM traffic, so the LUNs pointed to by any of the RDMs on the virtual machine must not be masked against its WWNs. When virtual machines do not have WWN assignments, they access storage LUNs with the WWNs of their host’s physical HBAs. By using NPIV, however, a SAN administrator can monitor and route storage access on a per virtual machine basis.
How NPIV Works?
When a virtual machine has a WWN assigned to it, the virtual machine’s configuration file (.vmx) is updated to include a WWN pair (consisting of a World Wide Port Name, WWPN, and a World Wide Node Name, WWNN). As that virtual machine is powered on, the VMkernel instantiates a virtual port (VPORT) on the physical HBA which is used to access the LUN.
Each VPORT is specific to the virtual machine, and the VPORT is destroyed on the host and it no longer appears to the FC fabric when the virtual machine is powered off. When a virtual machine is migrated from one host to another, the VPORT is closed on the first host and opened on the destination host.
Things to Know:
- NPIV can be used on virtual machines with RDM disks.
- The number of VPORTs that are instantiated equals the number of physical HBAs present on the host.
- Keep the RDM on the same datastore as the VM configuration file
- All the underline infrastructure support or aware of NPIV e.g (HBA, ESXi, SAN Fabrics Switches)
- Use HBAs of the same type, either all QLogic or all Emulex. VMware does not support heterogeneous HBAs on the same host accessing the same LUNs
- When configuring a LUN for NPIV access at the storage level, make sure that the NPIV LUN number and NPIV target ID match the physical LUN and Target ID.
- Does not Support vMotion
- Does not Support on DAS (Direct Attach Storage) Storage.
- Zoning must exist for both (physical host WWN and NPIV WWN) & all path should be zoned
Configuring NPIV on Virtual Machine.
Create a VM with Custom Configuration- > Click “Next”
Follow all steps required to create a custom virtual machine.
On the Select a Disk page, select “Raw Device Mapping” and click “Next”.
From a list of SAN disks or LUNs, select a raw LUN you want your virtual machine to access directly.
Select a datastore for the RDM mapping file. You can place the RDM file on the same datastore where your virtual machine files reside, or select a different datastore.
NOTE: If you want to use vMotion for a virtual machine with enabled NPIV, make sure that the RDM file is located on the same datastore where the virtual machine configuration file resides.
Follow the steps required to create a virtual machine with the RDM. On the Ready to complete page, select the “Edit the virtual machine settings” before completion check box and click “Continue”. The “VM Properties” dialog box opens.
Click the “Options” tab, and select “Fibre Channel NPIV”
Select “Generate new WWNs”.
Specify the number of WWNNs and WWPNs
NOTE: A minimum of 2 WWPNs are needed to support failover with NPIV. Typically only 1 WWNN is created for each virtual machine.
The host creates WWN assignments for the virtual machine
Register newly created WWN in the fabric so that the virtual machine is able to log in to the switch, and assign storage LUNs to the WWN