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Exchange 2010 - DAG and Circular Logging

Question
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We have an Exchange 2010 environment with a DAG setup with 2 hosts. We're thinking of enabling Circular Logging and was wondering if there's any downside to this?
From my perspective:
1) The chances of both servers going down will be slim, so the logs won't be used for DR purposes.
2) Circular Logging will free up 400-500 GB of space
3) If our backups fails and the logs doesn't get truncated, we won't have to worry about it stopping Exchange from functioning
Are there any major downside or pitfalls of enabling circular logging in a DAG? The only other question is that since the DAG is based around log shipping and replaying, I would assume that there's a mechanism in place to prevent the logs from being overwritten until it's been copied/replayed into the passive copy?
Wednesday, April 27, 2011 7:47 PM
Answers
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similar question as yours and some excellent answers
Wednesday, April 27, 2011 11:34 PM -
I would assume that there's a mechanism in place to prevent the logs from being overwritten until it's been copied/replayed into the passive copy?
This is correct.
Paul Cunningham (MCITP)
Blog: Exchange Server Pro
Book: Exchange Server 2003 to 2010 Migration GuideThursday, April 28, 2011 2:50 AM
All replies
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similar question as yours and some excellent answers
Wednesday, April 27, 2011 11:34 PM -
I would assume that there's a mechanism in place to prevent the logs from being overwritten until it's been copied/replayed into the passive copy?
This is correct.
Paul Cunningham (MCITP)
Blog: Exchange Server Pro
Book: Exchange Server 2003 to 2010 Migration GuideThursday, April 28, 2011 2:50 AM -
Hi Pham0329,
Quote "We're thinking of enabling Circular Logging and was wondering if there's any downside to this"
Why not, you can use circular logging in DAG model, this is one of the accepted solution when we remove requirement of VSS backup in DAG model. Only the thing is you have to define LAG copy interval value in DR DAG server so in case of DR you will have logs a DR site.
some org use it and some not as they have to keep backup for long retention time, So it's up to your managment decesion.
Some more information:
Log Truncation without Backups :
http://technet.microsoft.com/en-us/library/dd876874.aspx
Anil- Proposed as answer by Joseph Hwa Yang Tuesday, May 6, 2014 9:55 AM
Thursday, April 28, 2011 3:21 AM