beautypg.com

About pid mapping, Dynamic pid, Static pid – HP StorageWorks MSA 2.8 SAN Switch User Manual

Page 146: Dynamic pid static pid

background image

Updating Switches to the Core PID Addressing

146

Fabric OS Procedures Version 3.1.x/4.1.x User Guide

Note:

It is recommended not to use drivers that bind by PID. There are several routine

maintenance procedures which may result in a device receiving a new PID. Refer to

About PID Mapping for more information

.

About PID Mapping

A PID is a Port Identifier. PIDs are used by the routing and zoning services in
Fibre Channel fabrics to identify ports in the network. They are not used to
uniquely identify a device; this is done using the World Wide Name (WWN).

Some device drivers map logical disk drives to physical Fibre Channel
counterparts by PID. An example in a Windows HBA driver is “Drive E: = PID
011F00”. Most drivers can either dynamically change PID mappings or use the
WWN of the Fibre Channel disk for mapping, not the PID. For example, “Drive
E: = WWN 10:00:00:60:69:51:0e:8b”.

Dynamic PID

WWN or dynamic PID binding is most typically used. In this case, changing the
device’s PID does not affect the mapping. However, before updating the PID
format, it is necessary to determine whether or not any devices in the SAN bind by
PID (see

Evaluate the Fabric

).

Static PID

For those few drivers that use static PID binding, when the format is changed (PID
010F00), the mapping breaks and must be manually fixed. (The driver still has
“Drive E: = PID 011F00” but the actual device address is now “010F00”). This
can be done by rebooting the host or using a manual update procedure on the host.

To manually correct broken mapping due to static PIDs, refer to the following
sections for more detail:

Evaluate the Fabric

of this chapter discusses in more detail the process of

updating to the new PID format. This starts with evaluating a production SAN
to see which if any devices bind by PID. Then either an online or offline
update procedure is chosen to perform the actual update.

Frequently Asked Questions

provides a Q&A format to discuss the issues

surrounding a core PID format update.