Hi Chinh,
Yes, it is neccessary to backup these files.
Backup Exec (tm) 9.x or Backup Exec 10.0 for Windows Servers uses the Active File Exclusion feature to eliminate the SQL Server and flat-files from the file system backup. This will prevent "in use - skipped" errors on the .LOG files.
You can refer to the following doument.
http://seer.support.veritas.com/docs/242688.htm
Corrupt data, bad blocks/sectors, and excessive fragmentation on a hard disk will cause an Advanced Open File Option (AOFO) backup to fail.
The I/O device error is only one of many errors that can occur because of this.
To resolve the issue:
Run the Windows Error Checking Utility, a disk defragmentation, and check the Windows Event Viewer Logs on the machine being backed up to find out what files are causing the error to occur.
This should resolve your issue.
Please write us back if we have not understood your problem.
Thanks.
Note : If we do not receive your reply within two business days, this post would be marked ?assumed answered? and would be moved to ?answered questions? pool.