Support for Multipath I/O

Applies To: Windows Server 2008

Multipath I/O (MPIO) is a feature that provides support for using multiple data paths to a storage device. Multipathing increases availability by providing multiple paths (path failover) from a server or cluster to a storage subsystem.

You must install MPIO if you will be enabling more than one read/write path from a server to a logical unit number (LUN) by assigning multiple Fibre Channel ports or multiple Internet SCSI (iSCSI) initiator adapters on that server to the same LUN.

To install the MPIO feature, in Server Manager click the Features node, and then click Add Features to start the Add Features Wizard.


To prevent data loss, ensure that the server supports MPIO before you enable multiple Fibre Channel ports or iSCSI initiator adapters for LUN access. If the server does not support MPIO, or if you are not sure, enable only a single Fibre Channel port or iSCSI initiator adapter.


if you will be enabling access to a LUN from a cluster, ensure that Failover Clustering has been properly installed on each server in the cluster, or data loss can occur. For more information about installing Failover Clustering, see

For more information about MPIO, see