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How To Change The MPxIO/STMS Controller Number In Solaris 10 (Does not Apply to Solaris 11) (Doc ID 1387457.1)

Last updated on OCTOBER 05, 2022

Applies to:

Sun Storage Traffic Manager Software - Version 4.6 and later
Solaris Operating System - Version 10 3/05 to 10 1/13 U11 [Release 10.0]
Information in this document applies to any platform.
***Updated 26 July 2015***


Some applications like Oracle RAC require that the MPxIO/STMS controller numbers are consistent  across multiple nodes.

In Solaris 11 controller 0 (c0) is now reserved for MPxIO.  This  insures that the controller number is always consistent across all nodes when MPXIO is enabled.
This c0 reservation is independent of mpxio enable/disable and independent of established /dev namespace.


The procedure below applies to all versions of Solaris  10 only.

In this scenario, after replacing a faulty HBA, the MPxIO controller number changed from the original c6 to c0. The goal is to change it back to c6.

Comparing the explorer before and after the HBA was replaced showed that the /dev/cfg links and /etc/path_to_inst are the same, and yet somehow the controller number changed. Hardware installation of the HBAs is exactly the same as the other Oracle RAC node. The /dev/cfg and /etc/path_to_inst are also exactly the same as the other node.

MPxIO is the official name for Oracle Solaris's native multipathing driver. It is not an acronym. In Solaris 8 and 9, the same feature was called Sun StorEdge Traffic Manager Software (STMS).


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