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Posts from the ‘SQL’ Category


SQL max worker threads Problem When Using VSS To Backup Numerous Databases

In our ongoing (sort-of pilot) migration from VMware vSphere 5.5 to Microsoft Hyper-V 2012 R2, we encountered a very concerning and puzzling issue with backups. The transition had been smooth for the most part and we used the project to bring aging Windows/SQL 2008 servers up to 2012 R2 and 2014, respectively. Two of our SQL environments had moved over just fine and were being backed up successfully with Microsoft Data Protection Manager 2012 R2 for the time being (other products are being considered, including Veeam). The third of such SQL environments ran into a host of VSS errors once its data was populated and a backup attempted.


DPM 2012 R2 – Job Failed

Background (before/after):

  • Hypervisor: vSphere 5.5 to Hyper-V 2012 R2
  • Guest OS: Windows Server 2008 to 2014
  • Backup product: EMC Avamar 7.0.1 to MS DPM 2012 R2
  • Backup method: Crash-consistent image to VSS-quiesced image


We had seen an occasional VSS-related backup failure from time to time in DPM, but most were tied to available disk space for the protection group (DPM doesn’t do so well with deduplication of images, so growing has been near-continual). Retrying didn’t make a difference this time, though. We restarted VSS writers and even took downtime to restart the VM. Still the same failure. Read moreRead more


SQL Server: Create Login (Case Sensitive) Issue

I discovered an issue the other day when trying to add logins to a SQL Server with the collation of Latin1_General_BIN.

The T-SQL Command used was:

The error I was receiving was:
Windows NT user or group ‘DOMAIN\username’ not found. Check the name again.

However, the username was very much valid.  What I then found if I changed the format to DOMAIN\Username (capital U) it began to work.  However, on other servers (with same collation), it rejected the capital U and wanted a lowercase U.  After doing some digging, it appears that at least with the Latin1_General_BIN collation (not sure about other collations, I would expect other case-sensitive collations would inhibit similar results) that Master remembers logins how they are created the first time for a specific server and must continue to be entered using the same case going forward.  This appears to be true even if you delete the login and try to re-create it, it still wants the original case (Master appears to cache is indefinitely).

When working with logins on a Latin1_General_BIN SQL Server make sure to be consistent when typing the case for logins.  If you can’t figure out what the correct case is supposed to be, it appears if you add the login with the GUI, it will auto change it to be the format that master remembers.


SQL 2008 SP2 Slipstream Issue

Now that SP2 for SQL 2008 has been released it is time to update our SQL 2008 slip-streamed installation files.  The slipstream process is the same, but I did run into one bug once the process was completed.  There appears to be a bug that when you have a slip-streamed version of SQL 2008, the installation cannot be run from a network drive when .NET 4 has been installed.  The following error may be received when attempting to launch setup.exe.

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