5 Painful Backup & Recovery Mistakes (and how to avoid them)

Hosted by David Gugick and David Swanson, Dell

May 2, 2013

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Agenda

• Speaker Introductions

• Backup & Recovery Concepts in One Slide

• The 5 6 mistakes

• Resources

• Q & A

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David Swanson

• Database Systems Consultant, Dell

• david.swanson@quest.com

David Gugick

• Product Management, Data Protection, Dell

• david.gugick@quest.com

• @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