2. Paul Filmalter PFE Microsoft DAT313

3. Agenda Setting the Scene What’s New In Database Mirroring in SQL Server 2008 Tips and Tricks Summary

4. Setting the Scene Witness

5. Setting it up

6. Agenda Setting the Scene What’s New In Database Mirroring in SQL Server 2008 Tips and Tricks Summary

7. Improvements in 2008 Log Stream Compression Works with both async and sync Good network, local = minimal/no improvement Will see more improvements with “bad” networks, distance Reduces send queue Function of the transactions, not the network Tradeoff: CPU hit on principal and mirror On by default (Trace Flag 1462 to turn off)

8. Log Stream Compression Measuring Database Mirroring: Log Bytes Sent/sec (uncompressed) Database Mirroring: Log Compressed Bytes Sent/sec Databases: Transactions/sec SQL Statistics: Batch Requests/sec Processor: % Processor

9. Log stream compression

10. Improvements in 2008 Data Page Corruption Recovery 823, 824, 829 error encountered SQL Server will read partner Good copy of page will replace bad copy

11. Recovery from corruption with database mirroring

12. Improvements in 2008 Backup Compression Enterprise Edition only, but can restore compressed backups on all editions Reduces initialization time File sizes smaller Quicker copy time Watch the CPU

13. Agenda Setting the Scene What’s New In Database Mirroring in SQL Server 2008 Tips and Tricks Summary

14. Number of Databases … 10 DBs is a recommendation, not a limitation Customers ARE doing more than that Will depend on workloads I/O Threads CPU Memory More headroom with 64-bit

15. Failover Clustering and Database Mirroring Compliment each other Instance vs. database protection Age old question: asynchronous or synchronous? Considerations Most want clustering to be the primary HA feature Challenge: database mirroring failover is generally faster than a cluster failover (Timeout)

16. Using a Mirror for Reporting Done via snapshots Must be refreshed Can make the mirror more useful – not just a standby Downside: licensing General tip: watch I/O use – do not want to impact the mirror if your main goal is availability

17. Creating snapshots with database mirroring

18. Using DBM to Upgrade 2005->2008 Minimal downtime Unconfigure Witness Must be synchronous (no automatic failover) Use SQL Server 2005 SP2 CU5 (or later)

19. Upgrading from SQL Server 2005 to 2008 using database mirroring

20. Gotchas/Tips/Tricks 1 Application Watch transaction size Failover Partner in connection string Make sure you have good networks Use aliases in connection string if using failover partner Restoring the principal database Cannot happen while in a mirroring session either from a backup or a snapshot

21. Gotchas/Tips/Tricks 2 Initial configuration Possibly configure log shipping, then convert to DBM Transactional replication stops if DBM paused Prevents Subscriber from getting ahead of mirror Trace flag 1448 (2008) – overrides behavior 2005 – KB937041 (hotfix for SP2, then TF) T-log growth and backup affected

22. Gotchas/Tips/Tricks 3 Disk configuration Need good I/O performance; can be a bottleneck I/O on mirror may be higher than principal (by design) Trace Flag 3499 to alter I/O behavior (DO NOT USE UNLESS TEST THOROUGHLY) – will delay failover Logged operations and maintenance – effect on principal’s log

23. Agenda Setting the Scene What’s New In Database Mirroring in SQL Server 2008 Tips and Tricks Summary

24. Database mirroring can improve a database’s availability with minimal to no loss of data Database mirroring has improved with SQL Server 2008 Log stream compression can be helpful Do proper monitoring Need good configurations and hardware (esp. network and disk)

26. South African SQL Server Usergroup Meet monthly, 3 rd Tuesday evening at Microsoft’s Offices in Bryanston Current leads: Paul Filmalter and Gail Shaw

27. www.microsoft.com/teched International Content & Community http://microsoft.com/technet Resources for IT Professionals http://microsoft.com/msdn Resources for Developers www.microsoft.com/learning Microsoft Certification & Training Resources Resources Required Slide Speakers, TechEd 2009 is not producing a DVD. Please announce that attendees can access session recordings from Tech-Ed website. These will only be available after the event. Required Slide Speakers, TechEd 2009 is not producing a DVD. Please announce that attendees can access session recordings from Tech-Ed website. These will only be available after the event. Tech ·Ed Africa 2009 sessions will be made available for download the week after the event from: www.tech-ed.co.zawww.tech-ed.co.za

28. Additional Resources External Resources SQL Server Customer Advisory Team blog 2005 Database Mirroring Best Practices and Performance Considerations 2005 Database Mirroring Best Practices and Performance Considerations whitepaper Configuring Database Mirroring with SQL Server 2008 PowerShell Configuring SharePoint and Database Mirroring Configuring SharePoint and Database Mirroring whitepaper Database Mirroring and Log shipping Working TogetherDatabase Mirroring and Log shipping Working Together whitepaper Implementing Application Failover with Database MirroringImplementing Application Failover with Database Mirroring whitepaper SQL Server Replication: Providing High Availability using Database MirroringSQL Server Replication: Providing High Availability using Database Mirroring whitepaper SQL Server 2008 Business Value Calculator: www.moresqlserver.com

29. SQL Server Community Resources Become a FREE PASS Member: www.sqlpass.org/RegisterforSQLPASS.aspx www.sqlpass.org/RegisterforSQLPASS.aspx Learn more about the PASS organization www.sqlpass.org/www.sqlpass.org/ Additional Community Resources SQL Server Community Center www.microsoft.com/sqlserver/2008/en/us/community-center.aspx www.microsoft.com/sqlserver/2008/en/us/community-center.aspx TechNet Community for IT Professionals http://technet.microsoft.com/en-us/sqlserver/bb671048.aspx Developer Center http://msdn.microsoft.com/en-us/sqlserver/bb671064.aspx SQL Server 2008 Learning Portal http://www.microsoft.com/learning/sql/2008/default.mspx http://www.microsoft.com/learning/sql/2008/default.mspx Connect: Local Chapters, Special Interest Groups, Online Community Share: PASSPort Social Networking, Community Connection Event Learn: PASS Summit Annual Conference, Technical Articles, Webcasts More about the PASS organization www.sqlpass.org/www.sqlpass.org/ Connect: Local Chapters, Special Interest Groups, Online Community Share: PASSPort Social Networking, Community Connection Event Learn: PASS Summit Annual Conference, Technical Articles, Webcasts More about the PASS organization www.sqlpass.org/www.sqlpass.org/ The Professional Association for SQL Server (PASS) is an independent, not-for-profit association, dedicated to supporting, educating, and promoting the Microsoft SQL Server community.

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31. © 2009 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION. Required Slide