8x00 family of Disk Arrays 4.02.00 Installation and Reference Guide

3 Support for load balancing in Microsoft

Cluster Server environments for Windows

Server 2003

This section describes the following:

• Enabling or disabling support for load balancing in MSCS environments

• Recovering inaccessible disk devices

By default, in HP MPIO EVA DSM, load balancing is enabled in Microsoft Cluster Server (MSCS)

environments. The MSCS uses SCSI-2 reservations to synchronize access to the cluster-managed

devices. However, HP MPIO EVA DSM provides a feature to support load balancing for all HP disk

arrays that support the SCSI-3 persistent reservations management method by mapping the MSCS-issued

SCSI-2 reservations to SCSI-3 persistent reservations.

HP MPIO EVA DSM supports load balancing in MSCS environments only under the following conditions:

• All nodes in the cluster must have the same version of the HP MPIO EVA DSM installed.

• Support for load balancing in MSCS environments must be enabled on all cluster nodes in the HP

MPIO EVA DSM.

• The disk array containing the cluster resources must support the SCSI-3 persistent reservations.

You can enable or disable the load balancing support in MSCS environment anytime after the HP

MPIO EVA DSM installation.

NOTE:

• Contact HP technical support for details on disk arrays and the firmware revisions that support

persistent reservations.

CAUTION:

You must have the same setting for the load-balancing feature on all the nodes in a cluster. If the

setting is not consistent across all cluster nodes, the cluster node failover functionality can be impaired.

Enabling or disabling support for load balancing in MSCS

environments

You can enable or disable the load balancing support in MSCS environment in HP MPIO EVA DSM

using any one of the following methods.

Method 1:

HP MPIO Full Featured DSM for P6x00 family of Disk Arrays 4.02.00 installation and reference

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