Multi-pathing issues with IBM DS4000 Storage Subsystems

The LUN bouncing condition was occurring when requests were being sent to a DS4000 controller to move a LUN to an alternate path and the same request was also being sent from the alternate path to move the same LUN to the primary path causing the LUN to be moved back and forth for a period of time.

IBM currently recommends the Qlogic ql2x00.ham version 6.90h however this driver does not work with 6.16 (however the older 6.15 does work). To make the 6.16 firmware work requires the Qlogic driver version 6.90o or later (dated December 8, 2006)

There is a patch for NetWare 6.5 SP5 however it is not supported at this time on SP6. That patch can be found at https://download.novell.com/Download?buildid=TAw0FD_HnnE~~

This was particularly seen with arrays running 6.16 firmware where the NetWare 6.5 SP5 or SP6 nodes take minutes plus to start and then still do not support multi-path correctly. The 6.16 range of firmware is only used with the EXP810 Fibre SCSI trays that house 4 GB Fibre disks. If the Array hosts EXP100 (SATA) or EXP710 (2GB Fibre) trays and uses the 6.15 firmware then the existing drivers function correctly

example startup.ncf

SET Multi-path Support = ON

LOAD ACPI.PSM

LOAD IDECD.CDM

LOAD LSIMPE.CDM

LOAD SCSIHD.CDM AEN

LOAD IDEATA.HAM PORT=1F0 INT=E

LOAD ADPT160M.HAM SLOT=10010

LOAD ADPT160M.HAM SLOT=10011

LOAD QL2x00.HAM SLOT=4 /LUNS /allpaths /portnames /xretry=12 /maxluns=64

LOAD QL2x00.HAM SLOT=5 /LUNS /allpaths /portnames /xretry=12 /maxluns=64

Note: The AEN after the SCSIHD.CDM and the LSIMPE.CDM is the first driver loaded.