Circular Logging in SBS 2011
Posted on 2012-04-06
Should circular logging be turned on in Exchange 2010 on a SBS 2011 box?
I know it was on by default when we first installed the server.
Now it is off - maybe a MS update turned it off - it was on and we did not change it.
We have had issues with the number of log files growing huge (currently the folder that houses the log files is 5GB - 5,728 files).
We paid MS for a support incident - very expensive and got someone who I don't think was all that experienced - he said in an SBS 2011 environment it should be enabled.
Very confused about this as MS states this in the their help file...
"You can configure Exchange to save disk space by enabling circular logging. Circular logging allows Exchange to overwrite transaction log files after the data that the log files contain is committed to the database. However, if circular logging is enabled, you can recover data only up until the last full backup. For example, you can enable circular logging when using Exchange native data protection, in which you don't make backups. To prevent log buildup, you need to enable circular logging.
In the standard transaction logging used by Exchange 2010, each database transaction is written to a log file and then to the database. When a log file reaches one MB in size, it's renamed, and a new log file is created. Over time, this results in a set of log files. If Exchange stops unexpectedly, you can recover the transactions by replaying the data from these log files into the database. Circular logging overwrites and reuses the first log file after the data it contains has been written to the database.
In Exchange 2010, circular logging is disabled by default. By enabling it, you reduce drive storage space requirements. However, without a complete set of transaction log files, you can't recover any data more recent than the last full backup. In a normal production environment, circular logging isn't recommended.
For information about how to enable and disable circular logging, see Configure Mailbox Database Properties."
We are getting good backups with the SBS built-in backup program.
Any help would be appreciated. Thank you.