Backup to remote Azure URL failed due to throttling at VM level

  There are multiple levels of throttling with Azure.  You can get throttled at disk level, storage account level or VM/host level.    These types of throttling can manifest into something that may not be that obvious. Recently we received a call from customer who was backing up databases from Azure VM to Azure blob storage. …


SQL 2016 — Why can’t I STRETCH my database (I have the right user name and password)?

Recently we got a call from customer who was trying to enable stretch database but repeatedly got errors like below: Oct 14 2016 13:52:05 [Informational] TaskUpdates: Message:Task : ‘Configure Stretch on the Database stretchdb6’ — Status : ‘Running’ — Details : ‘Task failed due to following error: Microsoft.SqlServer.Management.Smo.FailedOperationException: Alter failed for Database ‘stretchdb6’.  —> Microsoft.SqlServer.Management.Common.ExecutionFailureException:…


Default auto statistics update threshold change for SQL Server 2016

Lately, we had a customer who contacted us for a performance issue where their server performed much worse in SQL Server 2016 following upgrade.  To show us as an example, he even captured a video.  In the video, he showed that the session that was compiling the query had multiple threads waiting on LATCH_EX of…


Proxy settings & backup to URL (Azure blob storage)

    With so many users new to Azure, Sometimes an issue appears more complex than it really is.  If you back up your databases to Azure blob storage but your company uses proxy servers for internet access, you will need to configure backuptoURL.exe.config  per SQL Server Backup to URL Best Practices and Troubleshooting.  We…


Why “SQL Server Configuration” section on my Azure Virtual Machine is not available?

If you created an SQL Server VM via azure portal, there will be a section called “SQL Server Configuration” which was introduced via blog “Introducing a simplified configuration experience for SQL Server in Azure Virtual Machines”. Here is a screenshot of that setting.  It allows you to configure various things like auto backup, patching or…


Unable to connect to SQL Server on azure VM due to an extra NSG applied to subnet

If you need to open up your SQL Server on an Azure VM to public internet access, you need to look no further than this document Connect to a SQL Server Virtual Machine on Azure (Resource Manager). It has very detailed step-by-step instructions. On a very high level, here are steps In your VM, create…


Why am I getting NULL values for query_plan from sys.dm_exec_query_plan?

Recently we got a customer who called in and wanted to know why he received NULL for query_plan when querying sys.dm_exec_query_plan.   This customer referenced a blog from  In that scenario, you will get NULL for query_plan if there are any statements involving temp tables that have not been executed for the first time.   For…


Why do I get the infrastructure error for login failures?

In the past few weeks, I saw this error come across quite a bit and thought I will provide an explanation for the reasons why we generate this error. It is very possible that you came across either one of the flavors of the two error messages shown below: 2016-07-08 23:53:59.63 Logon       Error: 18456, Severity:…


Tips & Tricks on ‘cloning’ Azure SQL virtual machines from captured images

While we have documentation on how to create a VM from captured image under “How to capture a Windows virtual machine in the Resource Manager deployment model”, it doesn’t address some specifics on SQL Server.  We have seen more and more users wanting to configure SQL Server and a set of databases so that they…


New memory grant query hint MIN_GRANT_PERCENT came to rescue

In SQL Server 2012 SP3, we made supportability improvements in the memory grant space. One of the features (  is allow you to hint your query (MIN_GRANT_PERCENT and MAX_GRANT_PERCENT), giving you much more granular control. There are additional columns related memory grants in sys.dm_exec_query_stats ( and query_memory_grant_usage extended events to help troubleshoot memory grant issues….