IBM TotalStorage DS300 Best Practices Manual page 523

Note: It is important for this description that the Array-1 of the logical drive
WOLGA-BOOT is owned by controller A. When the alternate controller owns the
array of the logical drive the port names needs to be changed to reflect that
the access goes over a port of controller B and not A.
Generally it is also possible to use controller B to boot from.
Access control was also defined during the creation of the array and logical
drives. Both initiators have access to all five logical drives. The setup of the
TotalStorage DS400 and the SAN switches are done.
The current setup allows to see each defined logical drive four times. During
installation of Microsoft Windows all drives seen separately because Windows
has no knowledge about multiple paths to the same disk. There is no
multipathing driver or software running at this time. The result is a kind of shared
storage. The multipath driver or software can be installed after the installation
was success full.
Disconnecting one HBA dose not solve the issue with seeing disks multiple times
because one HBA has access to controller A and controller B and the logical
drive is seen over both controllers. Three ports of the TotalStorage DS400 can be
disconnected together with one HBA so that every defined logical drive on the
TotalStorage DS400 is seen only one by the host. This is very unpractical in
productive environments.
Reconfigure the zoning on the SAN switches might be used, but this affects also
all systems connected to the switch and I/O might be interrupted.
With help of the CLI the access of an initiator to a port of the TotalStorage DS400
can be restricted. Per default a initiator can access all four ports of the
TotalStorage DS400. This has also the advantage the target will be seen but no
logical drives. For problem determination and verification that the cabling is
correct this steps need not to be reverted. The steps below explain the tasks to
restrict the available logical drives seen by the host during installation of
Windows Server 2003 Enterprise Edition.
Note: The described tasks can only be performed from the command line
interface (CLI).
1. Use a Telnet to connect to one of the management IPs of the DS400. The
examples below showing controller A. Logon with administrative rights.
Chapter 9. TotalStorage DS400 installation
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