7. Define the device class in the IBM Spectrum Protect Server for the library (Example 13-8). 

tsm: SERVER1>define devclass ptvtldevclass library=ptlibrary devtype=lto estcapacity=100000M format=ultrium3 ANR2203I Device class PTCLASS defined. 

8. The remaining tasks vary for each client environment. You must create storage pools by using the device class that is configured for the VTL. Then, you must update the management classes and backup/archive copy groups. After these steps are complete, you can explore the advantages of the ProtecTIER product. 

## 13.2.15 Updating to a VTL library type 

You can update an existing small computer system interface (SCSI) library to a VTL library type by running the following command: 

update library <libname> LIBTYPE=VTL 

Updating the library to a VTL library type enables ProtecTIER to make more accurate assumptions and skip unnecessary SCSI validations. Depending on the operating system, you might run into limitations, such as 300 - 500 maximum drives. 

Setting the LIBTYPE=VTL  also eliminates the restriction of defining only 120 tape drives when you use IBM Spectrum Protect and the ProtecTIER product. This feature is available only with Tivoli Storage Manager V6.3 or later. If you have a previous version of Tivoli Storage Manager, you might want to review APAR IC66116  ( Large number of tape drives can cause volume mounts to perform slowly) at the following website: 

http://www.ibm.com/support/docview.wss?uid=swg1IC66116 

Updating the library:  The UPDATE LIBRARY  function does not support mixed media, such as drives with different device types or device generations in the same library (LTO2 and LTO3). Also, this function requires that online paths be defined for servers and storage agents to all drives in the library. If paths are missing or offline, the performance levels degrade to the level of the SCSI library. 

## 13.2.16 Defining and deleting IBM Spectrum Protect libraries with many drives 

Version 6.3 introduced the PERFORM LIBACTION  command, which automatically defines the library/path/drive structure in a single command. This action is helpful when you use the ProtecTIER product because it usually contains many drives. When you run the PERFORM LIBACTION  command, complete the following steps: 

1. Create a path to the library. 

2. Scan for all drives that belong to the library and define all drives that are found in the library. 

3. Define paths to the drives found in the library, respecting the virtual tape drive numbering. 

Use IBM Spectrum Protect to define and delete IBM Spectrum Protect libraries (VTL and SCSI library types only) that contain many drives by running the following command: 

PERFORM LIBACtion <library_name> device=xxx action=define 

