This article covers the functionality and configuration of the LUN shrink feature on a Windows 2008.

Microsoft Windows Server 2008 has the capability to shrink volumes. Volume space reduction is done via Windows Disk Administration functionality. The LUN space reclamation is done via the diskraid.exe utility in conjunction with the Virtual Disk Service (VDS) provider supplied by the array vendor to process the shrink request. Host I/O may be present during the shrink operation, but may be pended at certain points.

You can refer to the following steps to configure LUN shrink on a Windows 2008:

1. Install the Host Agent and Naviseccli software on the server. You can download thesesoftware on support.emc.com.

2. Install the EMC VDS provider and Solutions Enabler.  You can download these software on support.emc.com.

3. Install DiskRAID.exe on Windows 2008. You can download it on Microsoft office website.

4. Configure the Solution enabler for discovering CLARiiON.

                  

        a. Add the Solutions Enabler base license as follow:

             C:\program files\EMC\SYMCLI\bin\symlmf

              register License Key (y/ )?   y

              Enter License Key:  xxxx-xxxx-xxxx-xxxx

       b. Within Solutions Enabler run the authorization for each SP that is connect to the host:

        C:\program files\EMC\SYMCLI\bin > symcfg authorization add –host IP_Address_Of_SPA  –username xxxx –password xxx

        C:\program files\EMC\SYMCLI\bin > symcfg authorization add –host IP_Address_Of_SPB  –username xxxx –password xxx

        C:\program files\EMC\SYMCLI\bin > symcfg authorization add –host IP_Address_Of_The_Server  –username xxxx –password xxx

                  

        c. Within Solutions Enabler discover connected arrays:

         C:\program files\EMC\SYMCLI\bin > symcfgdiscover –clariion

         C:\program files\EMC\SYMCLI\bin > symcfg list –clariion

5. Shrink the disk in Disk Management of Windows Server.

6. Use DiskRAID.exe on Windows Server to free up the disk space from the server side.

           a. DISKRAID>  list provider   #iVDS provider is for iSCSI, VDS provider is for FC

           b. DISKRAID>  list subsystems

           c. DISKRAID>  detail provider   #Use this command to check that you are selecting the correct subsystem.

           d. DISKRAID>  list lun

            e. DISKRAID>  select lun x    #Select the LUN that you want to shrink

           f. DISKRAID>  detail lun     #Compare the LUN name and Identifier here with the LUN name and UUID in the Unisphere GUI, make sure you are selecting the correct LUN.

           g. DISKRAID>  shrink lun size=xxGB     #The space can be released after executing this command.

7. Check the LUN capacity to confirm that the LUN size has been decreased. If the command has been successful executed, you will see the following output:

             DiskPart successfully shrunk the volume by: xxx MB