Backup runs very slow on IDE-based (ATAPI) tape drives and verification operations may not work

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This article was previously published under Q263480

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SYMPTOMS

When you perform a backup to an IDE-based (ATAPI) tape drive, the backup times are excessively long. A process that typically take minutes to complete, may take hours. During a tape verification operation, you may also receive a Plug and Play surprise removal error message against the tape drive, which causes the backup verification operation to not work.

The Plug and Play surprise error message may look similar to the following example:

Unsafe Removal of Device

You have unplugged or ejected a device without stopping it. Unplugging or ejecting devices without first stopping them can often cause your computer to crash and lose valuable data. To safely unplug or eject any of the following devices, first use the Hardware wizard in the Control Panel to stop the device.

Tape drive -or- CD-ROM drive.

If you frequently need to unplug this device, Windows can give you an icon on the taskbar to quickly unplug or eject your device. If you would like to use this option, check the following:

Show Unplug/Eject icon on the taskbar.

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CAUSE

This behavior occurs because the tape drive is attached to an IDE channel that also contains a CD-ROM. When a CD-ROM is present, the Windows 2000 CD-ROM driver polls the CD-ROM drive every second looking for media changes. This is done to allow the Autorun feature to work.

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RESOLUTION

To improve backup performance and eliminate possible Plug and Play surprise removal error messages, use one of the following workarounds:

Turn off the Autorun feature by using the steps in the following Microsoft Knowledge Base article:
967715 (http://support.microsoft.com/kb/967715/ ) How to disable the Autorun functionality in Windows
Move the tape drive or CD-ROM so that these two devices are located on separate IDE controllers.
Purchase a SCSI-based tape drive and controller listed on the Windows 2000 Hardware Compatibility List (HCL) to enhance reliability and performance of your backups.

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MORE INFORMATION

Because backup verification operations are read only, backup performs I/O requests to the tape drive more often and is the reason Plug and Play surprise removal error messages may be displayed when Autorun is enabled. This may result in Ntbackup reporting the following message during a verification operation in the Backup report:

Error: An inconsistency was encountered on the requested media.
Verify completed on 5/31/2000 at 5:22 AM.
Directories: xxx
Files: xxx
Different: 0
Bytes: xxx
Time: X minutes and Y seconds

After this error message is displayed, all additional verification operations are stopped, and the following error message is posted in the Application event log:

Event Type: Error
Event Source: NTBackup
Event Category: None
Event ID: 8009
Date: 5/31/2000
Time: 5:22:36 AM
User: N/A
Computer: Computername
Description:
End Verify to 'C:'

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