Create a LUN

Applies To: Windows Server 2008 R2

Storage Manager for SANs includes the Provision Storage Wizard, which you can use to create a logical unit number (LUN) on a Fibre Channel or iSCSI disk storage subsystem.

Before you create a LUN on a storage subsystem, verify that all the following requirements are fulfilled:

  • The storage subsystem supports Virtual Disk Service (VDS).

  • The VDS hardware provider for the storage subsystem is installed on your server.

  • There is storage space available on the storage subsystem.

  • If you want to assign the LUN that you create to a server or cluster in your storage area network (SAN), the server connections have been configured by using the instructions in Manage Server Connections.

  • If you want to assign the LUN to a cluster, the cluster has been fully configured by installing Failover Clustering.


To prevent data loss, make sure that each server is a member of only one cluster and that Failover Clustering has been installed on each server in the cluster. For more information about installing Failover Clustering, see

  • If the LUN that you are creating is on an iSCSI subsystem, and you want to assign that LUN to an iSCSI target, the iSCSI targets in your SAN have been configured by using the instructions in Manage iSCSI Targets.

  • If the server to which you will be assigning the LUN will access the LUN through more than one Fibre Channel port or iSCSI initiator, Multipath I/O has been installed and is running on that server.


Data loss can occur if you assign the LUN to a server that does not have Multipath I/O installed and that will access the LUN through more than one Fibre Channel port or iSCSI initiator. For more information, see Support for Multipath I/O (MPIO).

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

To create a LUN

  1. In the console tree, click LUN Management.

  2. In the Actions pane, click Create LUN.

  3. Follow the steps in the Provision Storage Wizard pages.

Additional considerations

  • If you create a LUN and do not choose to create a volume for it immediately (by using the Provision Storage Wizard), the disk associated with that LUN will be visible to the server that you assign it to, but it will be offline. Before you can create a partition or volume on that disk, you must first use Disk Management or DiskPart to bring the disk online. For more information about bringing a disk online, see:

  • The types of LUNs that you can create depend on the types of LUNs that are supported by each of your storage subsystems. For more information about LUN types, see Overview of LUN Types.

  • The LUN creation process may take several minutes or longer to complete, depending on the properties that you selected and the subsystem hardware.

Additional references