5 Painful Backup & Recovery Mistakes (and how to avoid them) Hosted by David Gugick and David Swanson, Dell May 2, 2013
Dec 18, 2014
5 Painful Backup & Recovery Mistakes (and how to avoid them)
Hosted by David Gugick and David Swanson, Dell
May 2, 2013
2
Agenda
• Speaker Introductions
• Backup & Recovery Concepts in One Slide
• The 5 6 mistakes
• Resources
• Q & A
3
David Swanson
• Database Systems Consultant, Dell
David Gugick
• Product Management, Data Protection, Dell
• @davidgugick
Your Hosts
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Backup & Recovery Concepts in One Slide
Recovery Model
• Full
• Bulk Logged
• Simple
Backup Type
• Full
• Differential
• Transaction Log
Scope
• Database
• File or Filegroups
• Partial Quick Hint: Instant File Initialization can greatly speed
up database recovery!
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5. Stung By Switching Recovery Modes
Change recovery model from Full to Simple
Change recovery model from Simple back to Full
Expect it to take effect immediately?
No! Not until Full (or differential) backup is taken Until then, T-Log backups fail
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Demo
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T-Log T-Log T-Log T-Log T-Log T-Log T-Log T-Log
T-Log T-Log T-Log T-Log T-Log T-Log T-Log T-Log
4. Breaking the Log Chain
• When recovering a database from a differential backup strategy, SQL Server requires that the differential backups match the differential base in the full backup
Full Non
COPY_ONLY Full
Differential Differential Differential
Dev Manager:
“Can you make
me a current copy
of production?”
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3. Throttling Performance with Bad Processes
Too many concurrent backups
Excessive VLFs in the transaction log file
Improper maintenance
Poor IO design always spoils the party
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2. Inadequate Checks & Preventative Maintenance
Not using CHECKSUM?
Not using DBCC
CHECKDB?
No long-term retention of backups.
There’s some danger in WITH
INIT
Improper retention with
differential backups
Not tracking failed backups
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1b. Thinking of Backup Compression as Only a Space Saver
Compression Backup space
savings
Backup speed savings
Recovery speed savings
Faster Storage Replication
Less work for dedupe appliance
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1a. Failure to Test for Disaster Recovery
Document!
Test procedures and for time
Are retention policies adequate?
Comprehensive fire-drills
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Resources - References • Instant File Initialization
– http://msdn.microsoft.com/en-us/library/ms175935.aspx – http://blogs.msdn.com/b/sql_pfe_blog/archive/2009/12/23/how-and-why-to-enable-instant-file-initialization.aspx – http://sqlskills.com/BLOGS/PAUL/post/Misconceptions-around-instant-file-initialization.aspx – http://sqlskills.com/blogs/Kimberly/post/Instant-Initialization-What-Why-and-How.aspx
• CHECKSUM – http://www.sqlmag.com/article/database-backup-and-recovery/advanced-backup-and-restore-options-129834
• Recovery Models and Transaction Log Management – http://msdn.microsoft.com/en-us/library/ms366344.aspx
• Virtual Log File (VLF) Performance Impact – http://blog.sqlauthority.com/2011/01/02/sql-server-reduce-the-virtual-log-files-vlfs-from-ldf-file/ – http://sqlblog.com/blogs/linchi_shea/archive/2009/02/09/performance-impact-a-large-number-of-virtual-log-files-part-i.aspx – http://sqlskills.com/BLOGS/KIMBERLY/post/Transaction-Log-VLFs-too-many-or-too-few.aspx – http://sqlblogcasts.com/blogs/tonyrogerson/archive/2007/07/25/sql-2000-yes-lots-of-vlf-s-are-bad-improve-the-performance-of-your-
triggers-and-log-backups-on-2000.aspx
• Backup Performance – http://www.quest.com/webcast-ondemand/pain-of-the-week-performance-tuning-for-backups-and-restores813358.aspx
• LiteSpeed – LiteSpeed Landing Page: http://www.quest.com/litespeed-for-sql-server/ – Tech Brief: Top 6 LiteSpeed Features DBAs Should Know About: http://www.quest.com/techbrief/top-6-litespeed-features-dbas-should-
know-about815805.aspx – What's New in LiteSpeed for SQL Server 7.1 Blog Post: http://communities.quest.com/community/litespeed/blog/2013/03/04/litespeed-for-
sql-server-v71-what-s-new – Webcasts and Events: http://www.quest.com/events/list.aspx?contenttypeid=15&prod=192
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Q & A
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Thanks