FIX: Compatible Tape Drives May Not Read SQL Server Dumps

ID: Q152414

The information in this article applies to:
BUG#: 13749 | 13753

SYMPTOMS

A SQL Server tape dump may not be usable on a similar tape drive if the two tape drives do not support the same tape marking mechanisms.


CAUSE

By default, SQL Server checks for tape marks using the following algorithm:

  1. Does the tape drive support Setmarks? If so, use Setmarks.


  2. Else does the tape drive support Filemarks? If so, use Filemarks.


If you dump to a tape drive that does not support Setmarks and then attempt to load the dump on a drive that does support Setmarks, SQL Server will not be able to load the dump. The same is true for the reverse scenario.


WORKAROUND

Starting with Service Pack 3, SQL Server now contains the trace flag 3206 that will reverse the SQL Server tape mark algorithm to the following:

  1. Does the tape drive support Filemarks? If so, use Filemarks.


  2. Else does the tape drive support Setmarks? If so, use Setmarks.



STATUS

Microsoft has confirmed this to be a problem in Microsoft SQL Server version 6.0. Microsoft is researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.


MORE INFORMATION

SQL Server uses tape marks to determine things such as the end of a dump during loading and where to begin appending to a tape during a dump.

For information about enabling trace flags, page 727 in Part 8 Troubleshooting; Chapter 24 Additional Problem-Solving Techniques, Using Trace Flags, in the "Administrator's Companion."

Additional query words: QIC Setmarks Filemarks 


Keywords          : kbhw kbprg SSrvGen kbbug6.00 
Version           : 6.0
Platform          : WINDOWS 
Issue type        :

Last Reviewed: March 27, 1999