Edit: Still good stuff.
Originally posted July 28, 2015 on AIXchange
Anthony English recently tweeted about world wide port names (WWPNs), linking to this series of slides last updated by Anthony Vandewerdt in 2013. When working with SAN zoning storage devices and servers, it’s important to identify every piece of hardware. For those who work with IBM storage devices, determining the WWPN ranges used by each storage model is much simpler, thanks to the IBM Storage WWPN Determination guide. Vanderwerdt’s two-year-old slides are version 6.6 of the guide. When version 6.5 came out in 2012, he posted this explanation:
If this guide is new to you, its purpose it to let you take a WWPN and decode it so you can work out not only which type of storage that WWPN came from, but the actual port on that storage. People doing implementation services, problem determination, storage zoning and day-to-day configuration maintenance will get a lot of use out of this document. If you think there is an area that could be improved or products you would like added, please let me know.
It is also important to point out that IBM Storage uses persistent WWPN, which means if a host adapter in an IBM Storage device has to be replaced, it will always present the same WWPNs as the old adapter. This means no changes to zoning are needed after a hardware failure.
The document starts by defining WWPNs and world wide node names (WWNNs). It then lists the WWNN/WWPN ranges used by IBM products:
A WWNN is a World Wide Node Name; used to uniquely identify a device in a Storage Area Network (SAN). Each IBM Storage device has its own unique WWNN. For DS8000, each Storage Facility Image (SFI) has a unique WWNN. For SVC and Storwize V7000, each Node has a unique WWNN.A WWPN is a World Wide Port Name; a unique identifier for each Fibre Channel port presented to a Storage Area Network (SAN). Each port on an IBM Storage Device has a unique and persistent WWPN.
– IBM System Storage devices use persistent WWPN. This means if an HA (Host Adapter) in an IBM System Storage Device gets replaced, the new HA will present the same WWPN as the old HA. IBM Storage uses a methodology whereby each WWPN is a child of the WWNN. This means that if you know the WWPN of a port, you can easily match it to the WWNN of the storage device that owns that port.
– A WWPN is always 16 hexadecimal characters long. This is actually 8 bytes. Three of these bytes are used for the vendor ID. The position of the vendor ID within the WWPN varies based on the format ID of the WWPN. To determine more information we actually use the first character of the WWPN to see which format it is… .
Vanderwerdt also links to this list of companies that are registered with IEEE.