HP Integrity VM 4.3 N-Port ID Virtualization - A brief overview
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Limits and limitations
This section captures the various limits that currently apply to the NPIV feature and the few restrictions associated with
it. These restrictions may be removed in future releases.
Table 1. NPIV Limits
Description Supported Limits
vHBAs (NPIV HBAs) per VM 8
Number of vHBAs per physical HBA 8
Number of paths per NPIV LUN 8
Number of LUNs per vHBA 2048
Number of NPIV LUNs per VM 2048
Additional caveats
• LUNs should be presented either as NPIV storage or as legacy AVIO storage, but not both.
When a VM is configured with a vHBA, the administrator should make sure that the VM does not see the same set
of LUNs through a legacy AVIO adapter. Doing so may result in data corruptions because the I/O stack in the VM
may not identify these two instances as the same LUN.
Example: Host H1 has a physical adapter FC1. A VM V1 is created on H1 and is assigned a vHBA called vFC1.
Suppose there is a set of LUNs A, B, and C that is visible to the VM through the vHBA and to the host through the
physical adapter FC1, it is not recommended that the LUNs A, B and C be assigned to V1 as legacy AVIO
devices.
NOTE:
It is recommended that LUNs assigned to VMs through vHBAs not be presented
to the host.
• NPIV HBAs cannot be added or deleted from a running VM.
• There is no support for legacy device special files.
Legacy device special files are not supported for NPIV LUNs. In order to get ioscan to list the LUNs and their
associated agile DSFs in a VM that is connected via NPIV, use “-nN” on the command line (see Figure 4).
Figure 4. Listing LUNs attached through an NPIV HBA
# ioscan –knNfC disk
Class I H/W Path Driver S/W State H/W Type Description
===================================================================
disk 3 64000/0xfa00/0x1 esdisk CLAIMED DEVICE HP Virtual Disk
/dev/disk/disk3 /dev/disk/disk3_p2 /dev/rdisk/disk3 /dev/rdisk/disk3_p2
/dev/disk/disk3_p1 /dev/disk/disk3_p3 /dev/rdisk/disk3_p1 /dev/rdisk/disk3_p3
disk 4 64000/0xfa00/0xf esdisk CLAIMED DEVICE HP HSV300
/dev/disk/disk4 /dev/disk/disk4_p2 /dev/rdisk/disk4 /dev/rdisk/disk4_p2
/dev/disk/disk4_p1 /dev/disk/disk4_p3 /dev/rdisk/disk4_p1 /dev/rdisk/disk4_p3