When running Exchange Information Store backups, you may receive warnings regarding circular logging. They should look like this:
Circular logging is enabled. Forcing a full backup.
Exchange's circular logging functionality truncates the logs after a certain amount of time has passed; as a result, our software is unable to determine what the last item backed up was. A full backup is forced as a result.
If the information store you are backing up contains a large mailbox database (>150GB), a full backup will take significantly longer than an incremental. As such, you may want to avoid running full backups when you don't need to. To change this you will need to disable circular logging.
Resolution
Circular logging is disabled, by default, for Exchange 2007, 2010, 2013, and 2016. When deciding to disable circular logging, please be aware of how that will affect your Exchange server. Also, any change to transaction logging will only take effect when the Microsoft Exchange Information Store service has been restarted or the mailbox databases are unmounted and remounted. To disable circular logging, use the methods below:
Exchange 2007
Run the following command in Exchange Management Shell (EMS) to disable circular logging for a specific storage group.
Set-StorageGroup -Identity "Storage Group" -CircularLoggingEnabled $false
...where Storage Group is the name of the storage group you are modifying. If you want to use the Exchange Management Console to change this setting follow this procedure:
- Start the Exchange Management Console.
- In the console tree, expand Server Configuration and click Mailbox.
- In the work pane, right-click the storage group for which you want to enable or disable circular logging, and click Properties. The <Storage Group Name> Properties dialog box appears.
- Clear the Enable circular logging check box.
- Click OK.
Restart the Microsoft Exchange Information Store service or dismount and remount the databases in the storage group to complete the process. Microsoft's documentation on this setting can be found here for Exchange 2007.
Exchange 2010
Run the following command in Exchange Management Shell (EMS) to disable circular logging for a specific mailbox database.
Set-MailboxDatabase -Identity "Database Name" -CircularLoggingEnabled $false
...where Database Name is the name of the mailbox database you wish to modify. If you want to use the Exchange Management Console to change this settings, follow this procedure:
- Start the Exchange Management Console.
- In the console tree, navigate to Organization Configuration and go to the Mailbox section within.
- In the results pane, go to the Database Management tab and select the database you want to configure.
- Right-click on the database and select Properties.
- In the Properties window, go to the Maintenance tab.
- Clear the Enable circular logging check box.
- Hit OK.
Restart the Microsoft Exchange Information Store service or dismount and remount the database to complete the process. Microsoft's documentation on this setting can be found here for Exchange 2010.
Exchange 2013
Run the following command in Exchange Management Shell (EMS) to disable circular logging for a specific mailbox database.
Set-MailboxDatabase "Database Name" -CircularLoggingEnabled $false
...where Database Name is the name of the mailbox database you want to change. If you would like to use the Exchange Administration Center (EAC) to change this setting, use these steps:
- Log into EAC as an administrator.
- Go to Servers and then Databases at the top of the page.
- Click on the mailbox database you want to edit and hit the Edit icon.
- Uncheck the box next to Enable circular logging and click Save.
Restart the Microsoft Exchange Information Store service or dismount and remount the database to complete the process. Microsoft's documentation on this setting can be found here for Exchange 2013.