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AOFO Warning

Level 3

Backing up files from a NAS to a tape, I got an AOFO intialization failure warning.  The whole message is:

 - AOFO: Initialization failure on: "D:". Advanced Open File Option used: Microsoft Volume Shadow Copy Service (VSS).
V-79-10000-11235 - VSS Snapshot error. Microsoft Volume Shadow Copy Service (VSS) cannot communicate with the writers. Check that the Volume Shadow Copy Service is started, and check the Windows Event Viewer for errors related to this service.

We don't use AOFO on this job, so I'm confused about that in general, but when I checked the VSS writers, everything was stable with no errors.

Possibly related: over the past 6 weeks or so, we've been getting occasional (once every 10 days or so?) job failures on a sharepoint system state backup with the exact same error message (except "System?State" in place of "D:" above).  The sharepoint failures never happen two days in a row, and the only abnormality is a VSS error in the log (Symantec support pointed us at a MS hotfix for the logged VSS error, which I haven't had a chance to install yet).

The NAS warning today was the first we've seen on that box, and there were no errors in the log on the NAS or the media server (other than warning logged for the job warning).


So, any ideas why we'd get an AOFO error on a straight file backup NAS-to-tape job?


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Never seen this on a NAS myself. Are you able to turn on AOFO when you back up the NAS, and if so, what are the results?

Level 3

Sorry for getting back to you so late.  AOFO isn't turned on in the first place.  This only happened that one day, so I'm still not sure if there's a problem or if it's related to the other identical errors or what.  I just thought I'd throw this out onto the forum to see if anyone else was getting similar errors.  I'll keep poking around and update this thread with any relevant information.

Level 5
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The above exception message can be seen when performing Full backups of the following database Agents: 
  • Agent for Microsoft SQL Servers
  • Agent for Microsoft SharePoint Servers
  • Agent for Enterprise Vault

This exception is generated after a backup has been performed of SQL databases that are set with a Recovery Model of "Full" or "Bulk-logged".  However , if it is set to "Simple" , it will not generate the exception. This is done by accessing the database properties >>> Option on SQL Server.

When it is set to "Full" , the transaction logs will be managed by Backup Application. When it is set to "Simple" , transaction logs will be managed by SQL itself. Drawback with setting it to "Simple" is , it will not allow point in time recovery for the database , therefore its recommended to set it to "Full" or " Bulked".

This exception will not occur on every backup of a SQL database.  This exception is generated after 11 Full backups of SQL Databases, the 12th backup will display this error message.

This exception is designed to help customers manage the size of SQL databases and transaction logs. Symantec recommends scheduling regular log backups of databases this will help keep the transaction logs at a manageable size.

For more information about SQL Recovery Modes, please visit the following Microsoft TechNet article below:

NOTE: This Exception was added in Backup Exec 2010, it was not in previous versions of Backup Exec.


Configure a log backup of the database(s) in question

For Microsoft SQL:

Create a backup with a Backup Method of  "Log - Back up Transaction Log".  This can be set in the Microsoft SQL section of the backup job properties.

For Microsoft SharePoint:

Create a backup with a Backup Method of "Log - Back up and truncate transaction Log".  This can be set in the Microsoft SharePoint section of the backup job properties.

For Enterprise Vault:

Create a backup with a Backup Method of "Incremental".  This can be set in the Enterprise Vault section of the backup job properties.

To configure this exception to show after a larger number of backups then the default number the following registry key on the Microsoft SQL Server will need to be adjusted.

Warning: The resolution of this issue requires the registry to be edited with the Windows registry editor. Incorrect use of the Windows registry editor can have disastrous results on a server operating system. Great care should be taken when making changes to a Windows registry. Registry modifications should only be carried-out by persons experienced in the use of the registry editor application. It is recommended that a complete backup of the registry and workstation be made prior to making any registry changes.

HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Backup Exec for Windows\Backup Exec\Engine\SQL Server\Number of Non-Log Backups Before Warning

The default value is a decimal value of 10

Increasing this value will increase the number of full database backups it will take to display the exception

Setting the value to 0 will disable this exception from ever occurring.  Symantec does not recommend setting this value to 0.

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Please don't plagiarise Symantec TNs...if you quote from it, reference it! Give credit where it's due wink