Symptoms
When you use a third-party backup software to perform a transaction log backup in Microsoft SQL Server 2012, a failed backup may result in breaking transaction log chain, and you cannot receive the error message. For example, if you have the following sequence in log backup:Success, Failure, Success It means the last Log Sequence Number (LSN) of the first backup does not match the first LSN of the second successful backup.
Resolution
After you apply this hotfix, you will receive a better error message that indicates a possible disconnection to the client. The error message resembles the following:
<DateTime> spid52 The log backup chain is broken. You must perform a full database backup before you can perform a log backup.
Note The failure is caused by some problem on the backup application after SQL Server has advanced the backup LSN. In this case, there will be a disconnection between the backup application and the SQL Server Engine. Because of the failure on its end, the backup application would not save the backup contents. But SQL Server assumes that it is done with this backup and moves forward. When the next transaction log backup is requested, the backup will contain information only beyond the advanced LSN but not the lost contents. Then you will receive the message that indicates the problem situation.
Service pack information for SQL Server 2012
To resolve this problem, obtain the latest service pack for Microsoft SQL Server 2012. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
2755533 How to obtain the latest service pack for SQL Server 2012
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
