You Really Should Stay Current on Cumulative Updates

I have encountered a Log Shipping error that I want to detail as an encouragement for staying current on SQL Server cumulative updates. First, a little background. The environment is SQL Server 2014 Standard edition with a physical machine as the primary and two secondaries, both virtual machines backed by a flash storage system.   SQL Server is on service pack 1, cumulative update 1. Log shipping had been configured in this environment for many months, but SQL Server 2008R2 was updated to SQL Server 2014 some months prior. The Log Shipping Restore job leaves the database in the Standby Mode so it can be queried for reporting purposes.

One evening I received the following error via database mail: “SQL Server Alert System: ’Severity 021’ occurred on \\MySecondary. An error occurred during recovery, preventing the database ‘MyDatabase’ from restarting. Diagnose the recovery errors and fix them or restore from a known good backup.” This was immediately followed by another email advising that the Log Shipping restore job had failed. Yet a third email was sent for error 9004 severity 16, explaining that an error occurred processing the log for “MyDatabase.” The message informed that I could restore from backup or rebuild the log. I connected to the SQL instance and saw that the database was in the restoring mode.

A quick internet search turned up the following two links.

https://support.microsoft.com/en-us/kb/2987585

https://support.microsoft.com/en-us/kb/2015753

The symptoms section of the first link seemed to fit my situation fairly well. I was unfamiliar with the fsutil command line utility. When I executed it against my environment the results indicated that the Bytes per Sector value was 512 and Bytes per Physical Sector returned “Not Supported.” The support article gave me two workarounds for addressing the issue.

• Move the transaction log file at the destination to a drive that has “Bytes per Physical Sector” set as 512 bytes.Note The Standby file can still be located on the drive that has “Bytes per Physical Sector” set as 4096 bytes.
• Restore the log backups without using the standby option. Instead of the STANDBY option, use the WITH NORECOVERY option during the restore operation.

Since my database was still in the restoring mode and the second URL indicated I had a damaged transaction log, I could not offline the database and relocate the file per the first recommendation. I also could not confirm how the bytes per sector value on the drive was configured anyway. The first article indicates that the issue was fixed in SQL Server 2014 SP1 CU2 and SQL Server 2012 SP2, CU7. Remember, I mentioned that the environment was on CU1 of SQL Server 2014 SP1. Unfortunately, that put me one update behind with respect to being protected from this situation.

Looks like I had one good course of action – restore from backup. I disabled the restore job, restored from a recent full backup and the most recent differential. I left the database in the restoring mode so I could re-enable the Log Shipping restore job. This would get the secondary back to Standby mode.

If you want to know when the latest updates for SQL Server are available, then I recommend saving the links below in your favorite web browser.  As this post demonstrates, be sure to read what the latest are about as soon as possible to see if they apply in your situation.

http://sqlserverbuilds.blogspot.com/

http://sqlserverupdates.com/

http://sqlblog.com/blogs/aaron_bertrand/default.aspx