Incompatibility Between Setmarks and Filemarks

• Microsoft Windows NT Server versions 3.5 and 3.51
• Microsoft SQL Server, versions 4.21a, 6.0 and 6.5

SYMPTOMS

When you try to restore data using SQL Load on a Tandberg 1.2-gigabyte (GB) drive, and the data has been backed up using SQL Dump with a WangTEK 525- megabyte (MB) drive, the load fails.

CAUSE

The Tandberg and WangTEK drives both produce outputs in QIC tape format. In the case described above, the load fails because the Tandberg drive reports the tape to be blank when data is really present.

The Tandberg drive has a new formatting feature called "setmarks," in addition to the old "filemarks" format. When the data was backed up using the WangTEK drive, filemarks format was used by the SQL Dump utility.

On the restore, the SQL Load utility defaulted to the new setmarks format when the Tandberg drive reported both formats were available. Requesting setmarks data from a filemarks formatted tape produced a result of "no data available."

RESOLUTION

As a temporary workaround to this problem, a modified tape driver is available. This driver reports filemarks only as available from the Tandberg drive.

STATUS

Microsoft has confirmed this to be a problem in Windows NT Server versions 3.5 and 3.51 and Microsoft SQL Server versions 4.21a, 6.0, and 6.5. A supported fix is now available, but has not been fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Product Support Services for more information.