Assume that you have a SQL Server 2017 installed on Linux. When you upgrade to SQL Server 2017 CU4 or later versions, and if the SQL Server Agent is not enabled, you may receive the following error messages:
Date/Time spid6s Error: 4860, Severity: 16, State: 1.
Date/Time spid6s Cannot bulk load. The file "FilePath\SqlTraceCollect.dtsx" does not exist or you don't have file access rights.
Date/Time spid6s Error: 912, Severity: 21, State: 2.
Date/Time spid6s Script level upgrade for database 'master' failed because upgrade step 'msdb110_upgrade.sql' encountered error 200, state 7, severity 25. This is a serious error condition which might interfere with regular operation and the database will be taken offline. If the error happened during upgrade of the 'master' database, it will prevent the entire SQL Server instance from starting. Examine the previous errorlog entries for errors, take the appropriate corrective actions and re-start the database so that the script upgrade steps run to completion.
Date/Time spid6s Error: 3417, Severity: 21, State: 3.
Date/Time spid6s Cannot recover the master database. SQL Server is unable to run. Restore master from a full backup, repair it, or rebuild it. For more information about how to rebuild the master database, see SQL Server Books Online.
Note: You might encounter the same issue when you try to downgrade your SQL Server instance from SQL Server 2017 RTM CU6 to CU5/CU4. The workaround suggested can be implemented for downgrade scenarios as well.
As a workaround for this issue, you can enable SQL Server Agent and restart SQL Server. As soon as the upgrade is complete, SQL Server Agent can be disabled again.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.