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

You must install MPIO on a server if it will access a logical unit number (LUN) through multiple Fibre Channel ports or multiple iSCSI initiator adapters. To install MPIO, follow the steps in the procedure that follows.

Caution

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 on the server.
Caution

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 http://go.microsoft.com/fwlink/?LinkId=86168.

Membership in the local Administrators group, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at http://go.microsoft.com/fwlink/?LinkId=83477.

To install MPIO

  1. In the Server Manager console tree, click the Features node.

  2. In the Features pane, under Features Summary, click Add Features.

  3. In the Add Features Wizard, select the Multipath I/O check box, and click Next.

  4. Follow the steps in the Add Features Wizard.

Additional references

  • Provision a LUN
  • Managing an Existing Shared Resource