"The log backup chain is broken" error when the log backup process fails in SQL Server

Applies to: SQL Server 2014 DeveloperSQL Server 2014 EnterpriseSQL Server 2014 Standard


In your Log shipping configuration, the log backup process may fail because of underlying storage and infrastructure issues. In this situation, the log backup process is retried, and this could overwrite a potentially valid log backup file. When this happens, you could experience a break in the log backup chain that may require you to perform a complete reinitialization of your Log shipping configuration. Depending on the size of your databases, this may be a very costly operation.

Additionally, errors that resemble the following are logged in the SQL Server error log:
Date/Time,Backup,Unknown,BACKUP failed to complete the command BACKUP LOG DatabaseName. Check the backup application log for detailed messages.

Date/Time,Backup,Unknown,Error: 3041 Severity: 16 State: 1.

Date/Time,spid326,Unknown,The log backup chain is broken. You must perform a full database backup before you can perform a log backup.

Date/Time,spid326,Unknown,The operating system returned error 170 (The requested resource is in use.) to SQL Server during a write at offset 0x00000009dde000 in file FilePath\FileName. Additional messages in the SQL Server error log and system event log may provide more detail. This is a severe system-level error condition that threatens database integrity and must be corrected immediately. Complete a full database consistency check (DBCC CHECKDB). This error can be caused by many factors; for more information see SQL Server Books Online.


The fix for this issue is included in the following cumulative updates and service pack for SQL Server:
Note After you apply this update, the intention is to remove the override of a valid transaction log backup. Therefore, this update introduces some additional validations to check whether the log chain remains unbroken.

Service pack information for SQL Server 2016

       Service Pack 2 for SQL Server 2016


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


Learn about the terminology  that Microsoft uses to describe software updates.