Failed to retrieve LSN information of the database. All differential backups based on this full backup are unreliable
Symptoms
The error is reported during backup ( VSS-Aware for SQL Server backup sets).
Cause
a) At the beginning of the backup the DS-Client will run a query to retrieve the LSN information so that it verifies if it is valid for the last full database backup.
b) The protected SQL instance is clustered and the backup set was not created by using the IP of the sql virtual cluster node.
c) the master database is included in the backup items list and the backup set is configured with "full+differential" database policy.
Workaround
a) If the backup set's database backup policy is set to "full always"then this error is not critical since it does not have to verify LSN with a full backup. If the backup set's database backup policy is set to "Full plus Differential" then this is important to resolve, ensure the following requirements are met:
- run the backup with a user that has sysadmin role assigned on the backup source SQL Server instance; configure the SQL Server backup set to use only Windows authentication ("access integrated with share") unless the Windows authentication is disabled on the backup source SQL Server instance.
- Ensure that the "SQL Server Browser" service is set to automatic and started on the backup target computer.
- Ensure that the "Remote Registry" service is set to automatic and started on the backup target computer (if running Windows 2012 and newer the "Remote Registry" service must be set to default "Automatic (Trigger Start)", just ensure it is not disabled, no need to start it, the DS-Client will start and stop it).
- If you are backing up a SharePoint Server database that is using Windows Internal Database you will not be able to connect remotely to verify the LSN information.
b) Use the the IP of the sql virtual cluster node to create the vss-aware backup set.
c) master database supports only full backups, either exclude the master database from the backup items list and create a second set ( configured with "full always" database backup policy) to protect the master database or change the database backup policy to "full always" for the current set.
d) the remote SQL Server instance may not be configured for remote connections. By default, SQL Server Express is installed (configured) only for local connections. By default, MS SQL Server is installed (configured) for remote connections, but this might have been changed. Workaround Use the SQL SQL Server Configuration Manager tool:
1. Start > All Programs > Microsoft SQL Server > Configuration Tools > SQL Server Configuration Manager:
2. Enable TCP/IP and Named Pipes; for each of the SQL Server instances you want to backup.