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25 Configuring and Deploying the Dell PS Series Multi-Path I/O Device Specific Module with Microsoft Windows | TR1036
A Using hardware initiators
In addition to the Microsoft iSCSI Initiator, the PS Series DSM supports hardware initiators. At the time of this
document, the Dell PS Series MPIO DSM supports the QLogic HBAs and iSCSI Offload for Broadcom CNA’s.
For information on these hardware initiators, reference the Dell PS Series Configuration Guide. When using
the Broadcom adapters with iSCSI Offload functionality, there are two methods to connect to iSCSI storage
through the adapter:
1) Using the Microsoft iSCSI Software Initiator, as described in this document.
2) Using the iSCSI functionality implemented within the adapter hardware itself. The Dell PS Series EHCM
service automatically prefers the hardware implementation if it is enabled and configured and iSCSI sessions
are established using these interfaces instead of the iSCSI software interfaces. To use the Microsoft iSCSI
software initiator instead, disable the iSCSI Offload functionality within the Broadcom Advanced Control Suite
(BACS).
The Multi-Path I/O DSM connection manager uses temporary CHAP credentials to create additional iSCSI
sessions to each target. As of this report, QLogic iSCSI HBAs do not support the use of CHAP credentials for
these sessions. Therefore, one of the following must be done for each target to use MPIO in these
configurations:
 Create a single access control record with the iSCSI initiator name of the host computer.
 Create a single access control record with an IP address range that includes all of the host
computer’s interfaces to be used for SAN.
 Create multiple access control records, one for each of the host computer's interfaces to be used for
the SAN, where each record contains a specific IP addresses.
When using MPIO with a PS Series group running firmware prior to 5.0, CHAP authentication must be
enabled. If the PS Series group is not configured to use local CHAP authentication, the server will receive
login errors when attempting to create MPIO sessions. Use the Group Manager GUI to enable local CHAP
authentication:
1. Click Group Configuration and open the iSCSI tab to display the options for iSCSI initiator
authentication.
2. Check Consult locally defined CHAP accounts first.