SMB 3.0 and SQL Server reading list

I've been exploring the SQL Server and SMB 3.0 possibilities. There is a large amount of information available on the subject. I've found these articles very useful. I'm interested in : Storage Option Database migration Failover Performance Server Message Block SMB File Share and SQL Server - An option to consider ... SQL Failover Cluster without Shared Storage – SQL Server 2012 and SMB Install SQL Server with SMB fileshare as a storage option Hardware and Software Requirements for Installing SQL Server 2012 : Storage Types for Data Files SMB 3.0. Best Feature of Windows Server 2012 How to Increase... Read more →

Troubleshoot SDDDSM error messages

Question: What is SDDDSM ? Often I see Event Log entries referencing SDDDSM , but can’t relate it back to SQL Server. How can I troubleshoot? Answer: SDDDSM is the Subsystem Device Driver Device Specific Module. The purpose is to support IBM storage devices . It’s a multipath IO system based on the Microsoft MPIO concepts. SDDDSM and MPIO work in conjunction supporting the multipath configurations. The general advice from IBM is to is to maintain a balanced use of all the paths and keep them active Use the datapath query adaptstats to view the number of reads and writes... Read more →

Error 5171 – mdf is not a primary database file

Question: I’m getting a SQL Server Error 5171 error , when trying to attach an mdf. The message is "mdf is not a primary database file". How can I fix this issue? An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo) D:\Data\mydb.mdf is not a primary database file. (Microsoft SQL Server, Error: 5171) Answer: My initial assumption is the database file is damaged. Confirming this assumption might be difficult. How to troubleshoot Error 5171 1) Check to see you have a valid backup. If so , restore from the backup device. Read more on disaster recovery. When you... Read more →

SQL Server - BobMgrGetBuf Sort Big Output Buffer write not complete after 60 seconds

Sometimes you may see this message in the SQL Server Error Log files BobMgrGetBuf Sort Big Output Buffer write not complete after 60 seconds It’s associated with IO subsystem issues , other common errors appearing and related are: SQL Server has encountered 1 occurrence(s) of I/O requests taking longer than 15 seconds to complete on file Read more on IO Requests taking longer than 15 seconds to - SQL Server DBA The message relates to large SORTS , probably the TempDB. Bob is the Big Output Buffer. Writres are heavy sequential and occur on transit tables .During the heavy sequential... Read more →

SQL Server – Pageiolatch_ex and how to reduce it

SQL Server Books online defines the SQL wait type pageiolatch_ex as “Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Exclusive mode. Long waits may indicate problems with the disk subsystem.“ The underlying causes typically relate to disk to memory , memory pressure and disk IO subsystem issues such as caching problems. The following scenario illustrates how this wait type arises. A user process will request some data which is not currently in the buffer cache. At that point – SQL Server will attempt to allocate... Read more →