Is your backup working properly?
Secondly, don't assume that your backup is always working. Don't just assume that because the tape has ejected from the drive, that everything is OK. Check in the log file in Backup Exec.
If you see the word Skipped against a QDR file, you can usually ignore this - QDR files are printing files. But if Skipped or In Use against a data file, such as \vision \data, then Vision 3 was still open or in use when the backup took place. If \vision\data\login.dbf was In Use, then this means somebody was logging on at a workstation.
The file SYS$LOG.ERR should show any errors.
What you are looking for is a message that the Job completion status (of the backup) was normal or successful.