FIX: Dump/Load May Fail to Work with Older Tape Drives and SCSI

A DUMP and LOAD may fail if a tape drive does not support variable block mode and the MaximumBlockSize reported by the GetTapeParameters API call is less than 32,768 bytes.

To work around this problem, dump databases, transaction logs and tables to disk devices, and then use the Windows NT Server Backup utility (located in Administrative Tools group) to back up the disk devices to tape.

Microsoft has confirmed this to be a problem in Microsoft SQL Server version 6.0 Service Pack 3.

Microsoft has confirmed this to be a problem in SQL Server 6.5. This problem has been corrected in Service Pack 5a for Microsoft SQL Server 6.5.For more information, click the following article number to view the article in the Microsoft Knowledge Base:For more information, contact your primary support provider.

With the SQL Server 6.5 Service Pack 5, you can now use trace flag 3207. This trace flag must be enabled for both the tape drives to work correctly with SQL Server 6.5 DUMP and LOAD statements. Trace flag 3207 works with both older and newer tape drive devices.

NOTE: To change the blocksize of a tape, the tape must be blank. If you want to make sure a tape is blank, you can use NTBACKUP to erase it. However, you may need to use the /NOPOLL switch on NTBACKUP.

For additional information, see the following article or articles in the Microsoft Knowledge Base:


Microsoft has created a utility called SQLTPTST to determine the capabilities of a tape drive. You can obtain this tool from Microsoft Product Support Services. Currently the file is at ftp://ftp.microsoft.com/bussys/sql/transfer/

The following errors may occur with this problem:

• The client receives the following error and the SQL Server error log does not contain any errors:
  
  Msg 3201, Level 16, State 1
  Can't open dump device '\\.\tape0', device error or device off line.
  Please consult the SQL Server error log for more details.
• The SQL Server errorlog contains the following errors:
  kernel Unnamed tape \\.\tape0 mounted on tape drive \\.\tape0
  kernel tprhdrs: HDR1 label not found
  kernel tbsreadhdr: Tape rejected