# Testing your setup by using Microsoft System Center DPM
You can back up your data to virtual tapes, archive the tapes, and manage your virtual tape library (VTL) devices by using Microsoft System Center Data Protection Manager (DPM). In this topic, you can find basic documentation on how to configure the DPM backup application for a Tape Gateway and perform a backup and restore operation.
For detailed information about how to use DPM, see the [DPM documentation](http://technet.microsoft.com/en-us/library/hh758173.aspx) on the Microsoft System Center website. For more information about compatible backup applications, see [Supported third-party backup applications for a Tape Gateway](Requirements.md#requirements-backup-sw-for-vtl).
**Topics**
+ [Configuring DPM to Recognize VTL Devices](#dpm-configure-software)
+ [Importing a Tape into DPM](#dpm-Import-tapes)
+ [Writing Data to a Tape in DPM](#dpm-write-data-to-tape)
+ [Archiving a Tape by Using DPM](#dpm-archive-tape)
+ [Restoring Data from a Tape Archived in DPM](#dpm-restore-tape)
## Configuring DPM to Recognize VTL Devices
After you have connected the virtual tape library (VTL) devices to the Windows client, you configure DPM to recognize your devices. For information about how to connect VTL devices to the Windows client, see [Connecting your VTL devices](GettingStartedAccessTapesVTL.md).
By default, the DPM server does not recognize Tape Gateway devices. To configure the server to work with the Tape Gateway devices, you perform the following tasks:
1. Update the device drivers for the VTL devices to expose them to the DPM server.
1. Manually map the VTL devices to the DPM tape library.
**To update the VTL device drivers**
+ In Device Manager, update the driver for the medium changer. For instructions, see [Updating the Device Driver for Your Medium Changer](resource_vtl-devices.md#update-vtl-device-driver).
You use the DPMDriveMappingTool to map your tape drives to the DPM tape library.
**To map tape drives to the DPM server tape library**
1. Create at least one tape for your gateway. For information on how to do this on the console, see [Creating Tapes](https://docs.amazonaws.cn/storagegateway/latest/tgw/GettingStartedCreateTapes.html).
1. Import the tape into the DPM library. For information on how to do this, see [Importing a Tape into DPM](#dpm-Import-tapes).
1. If the DPMLA service is running, stop it by opening a command terminal and typing the following on the command line.
**net stop DPMLA**
1. Locate the following file on the DPM server: `%ProgramFiles%\System Center\DPM\DPM\Config\DPMLA.xml`.
**Note**
The directory path might change depending on your version of System Center or DPM.
If this file exists, the DPMDriveMappingTool overwrites it. If you want to preserve your original file, create a backup copy.
1. Open a command terminal, change the directory to `%ProgramFiles%\System Center\DPM\DPM\Bin`, and run the following command.
**Note**
The directory path might change depending on your version of System Center or DPM.
```
C:\Microsoft System Center\DPM\DPM\bin>DPMDriveMappingTool.exe
```
The output for the command looks like the following.
```
Performing Device Inventory ...
Mapping Drives to Library ...
Adding Standalone Drives ...
Writing the Map File ...
Drive Mapping Completed Successfully.
```
## Importing a Tape into DPM
You are now ready to import tapes from your Tape Gateway into the DPM backup application library.
**To import tapes into the DPM backup application library**
1. On the DPM server, open the Management Console, choose **Rescan**, and then choose **Refresh**. The Management Console displays your medium changer and tape drives.
1. Open the context (right-click) menu for the media changer in the **Library** section, and then choose **Add tape (I/E port)** to add a tape to the **Slots** list.
**Note**
The process of adding tapes can take several minutes to complete.
The tape label appears as **Unknown**, and the tape is not usable. For the tape to be usable, you must identify it.
1. Open the context (right-click) menu for the tape you want to identify, and then choose **Identify unknown tape**.
**Note**
The process of identifying tapes can take a few seconds or a few minutes.
If the tapes don’t display barcodes correctly, you need to change the media changer driver to Sun/StorageTek Library. For more information, see [Displaying Barcodes for Tapes in Microsoft System Center DPM](resource_vtl-devices.md#enable-barcode).
When identification is complete, the tape label changes to **Free**. That is, the tape is free for data to be written to it.
## Writing Data to a Tape in DPM
You write data to a Tape Gateway virtual tape by using the same protection procedures and policies you do with physical tapes. You create a protection group and add the data you want to back up, and then back up the data by creating a recovery point. For detailed information about how to use DPM, see the [DPM documentation](http://technet.microsoft.com/en-us/library/jj628070.aspx) on the Microsoft System Center website.
By default, the capacity of a tape is 30GB. When you backup data that is larger than a tape's capacity, a device I/O error occurs. If the position where the error occurred is larger than the size of the tape, Microsoft DPM treats the error as an indication of end of tape. If the position where the error occurred is less than the size of the tape, the backup job fails. To resolve the issue, change the `TapeSize` value in the registry entry to match the size of your tape. For information about how to do this, see [Error ID: 30101](https://technet.microsoft.com/en-us/library/ff634181.aspx) at the Microsoft System Center.
**Note**
If your Tape Gateway restarts for any reason during an ongoing backup job, the backup job will fail. To complete the failed backup job, you must resubmit it.
## Archiving a Tape by Using DPM
When you archive a tape, Tape Gateway moves the tape from the DPM tape library to offline storage. You begin tape archival by removing the tape from the slot using your backup application—that is, DPM.
**To archive a tape in DPM**
1. Open the context (right-click) menu for the tape you want to archive, and then choose **Remove tape (I/E port)**.
1. In the dialog box that appears, choose **Yes**. Doing this ejects the tape from the medium changer's storage slot and moves the tape into one of the gateway's I/E slots. When a tape is moved into the gateway's I/E slot, it is immediately sent for archiving.
1. On the Storage Gateway console, choose your gateway, and then choose **VTL Tape Cartridges** and verify the status of the virtual tape you are archiving.
The archiving process can take some time to complete. The initial status of the tape is shown as **IN TRANSIT TO VTS**. When archiving starts, the status changes to **ARCHIVING**. When archiving is completed, the tape is no longer listed in the VTL.
## Restoring Data from a Tape Archived in DPM
Restoring your archived data is a two-step process.
**To restore data from an archived tape**
1. Retrieve the archived tape from archive to a Tape Gateway. For instructions, see [Retrieving Archived Tapes](retrieving-archived-tapes-vtl.md).
1. Use the DPM backup application to restore the data. You do this by creating a recovery point, as you do when restoring data from physical tapes. For instructions, see [Recovering Client Computer Data](http://technet.microsoft.com/en-us/library/hh757887.aspx) on the DPM website.
**Next Step**
[Cleaning up unecessary resources](best-practices.md#cleanup-vtl)