8x00 family of Disk Arrays 3.02.00 (AA-RW7SL-TE, March 2009)

3 Support for load balancing in Microsoft

Cluster Server environments for Windows

Server 2003

This section describes the following:

• Enabling support for load balancing in MSCS environments

• Disabling support for load balancing in MSCS environments

• Recovering inaccessible disk devices

By default, HP MPIO EVA DSM supports the No Load Balancing policy in Microsoft Cluster Server

(MSCS) environments. This is because 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.

NOTE:

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

reservations.

Enabling support for load balancing in MSCS environments

You can enable load-balancing support in MSCS environments while installing the HP MPIO EVA

DSM or anytime after the installation.

CAUTION:

You must enable the load-balancing feature on all nodes in the cluster. If the setting is not consistent

across all cluster nodes, the cluster node failover functionality can be impaired.

To enable load balancing at the time of installing HP MPIO EVA DSM, select Enable Load Balancing

in Cluster in the Configuration Settings window.

To enable load balancing after you have installed HP MPIO EVA DSM, complete the following steps:

HP MPIO Full Featured DSM for EVA4x00/6x00/8x00 family of Disk Arrays 3.02.00 23