In order for NPIV, and thus Virtual FC, to be used, the physical FC adapters must support NPIV. But this is the case with most FC adapters for POWER systems. Which FC adapters of a virtual I/O server support NPIV can be found out very easily with the command “vios lsnports“:

$ vios lsnports ms03-vio1
NAME  PHYSLOC                        FABRIC  TPORTS  APORTS  SWWPNS  AWWPNS  LABEL
fcs0  U78AA.001.VYRGU0Q-P1-C5-T1     1       64      62      2048    2023    Fabric1
fcs1  U78AA.001.VYRGU0Q-P1-C5-T2     1       64      53      2048    1977    Fabric1
fcs2  U78AA.001.VYRGU0Q-P1-C5-T3     1       64      62      2048    2023    Fabric2
fcs4  U78AA.001.VYRGU0Q-P1-C1-C1-T1  1       64      60      2032    2007    Fabric2
fcs5  U78AA.001.VYRGU0Q-P1-C1-C1-T2  1       64      58      2032    2018    Fabric1
fcs6  U78AA.001.VYRGU0Q-P1-C1-C1-T3  1       64      58      2032    2007    Fabric2
$

Only NPIV capable FC ports are listed. The column TPORTS (Target Ports) indicates the maximum number of N_Port IDs supported by the physical FC port, the column APORTS (Available Ports) indicates how many of them are currently still available. All listed FC ports support up to 64 N_Port IDs. The FC port fcs0 still has 62 unused N_Port IDs, so 2 of the 64 possible N_Port IDs are currently in use. Each virtual FC adapter requires 2 unique WWPNs (one of the two WWPNs is used for Live Partition Mobility). How many WWPNs a physical FC port supports is shown in the SWWPNS (Supported WWPNs) column, and how many of them are still available in the AWWPNS (Available WWPNs) column. The attribute label of the physical FC port is displayed in the LABEL column. However, this is only supported starting with IOS 3.1.1. If the IOS version is lower than 3.1.1, the character string “not_supported” is displayed. The label attribute can be set to any character string by the administrator. A useful value is the name of the FC fabric to which the FC port is connected. The label attribute can be set with the command “vios ​​chdev“:

$ vios chdev -P ms03-vio1 fcs0 label=Fabric1
$

The specified value is saved in the ODM on the virtual I/O server.

Tip: Set the attribute label for all physical FC ports, to the name of the connected FC fabric. This only has to be done once. It allows easy identification of the FC fabric a FC port is connected to. The label can also be used when mapping virtual FC adapters.

Each managed system has reserved a range of unique WWPNs (65536 WWPNs are reserved by default), which are used by the POWER Hypervisor for assigning unique WWPNs for each new virtual FC adapter. All of these reserved WWPNs have a common prefix (part of the WWPN). The unique prefix for WWPNs of a managed system and how many of the reserved WWPNs are still available, can be displayed with the command “ms lsfc“:

$ ms lsfc ms03
NAME  WWPN_PREFIX   NUM_WWPNS_REMAINING
ms11  C05076030ABA  65226
$

The prefix (and thus the WWPNs) always begins with C05076. This is a combination of “C” and the OUI “005076” for IBM. “C” indicates that it is a locally assigned WWPN.

The WWPN prefix can be used to identify the managed system on which a virtual FC adapter of an LPAR was originally created, even after numerous LPM operations.