12.1 Backup Strategies
12.1.3 Data restoration issues
All of the backup methods discussed will allow all critical data to be restored in the event of loss. The ability to restore data quickly is the true test of a good backup system. It is not enough to do nightly backups and not actually practice the restoration process. Users are not typically required to back up their own files. This is the job of the network administrator or network support staff. The network support staff must not only do regular backups but also test the backups periodically to verify they are good and they can restore from them. Backups should be checked regularly by conducting 'test restores' to verify the tapes are good and that the staff can perform the necessary steps to restore data under a variety of conditions. The time to verify the restore process is not when the hard drive fails and workers are wandering around with nothing to do and the boss is looking over your shoulder asking why it is taking so long.

To adequately test your ability to recover from data lost, the network support staff should be able to accomplish the following restoration tasks:

  • Restore a File - Thousands of files are typically backed up in any organization. If a user accidentally deletes or overwrites a file, an administrator should be able to find that file on the backup tapes and restore it to the user's home directory on a server or on their workstation.
  • Restore a Directory - If a directory is damaged, an administrator should be able to restore the entire directory structure with all subdirectories and files intact.
  • Restore a File System - If necessary, an administrator should be able to restore an entire file system.
  • Restore a Hard Drive - In the event of a total failure of a hard drive, an administrator should be able to recreate the contents of the original drive including the operating system, applications software, and data if applicable.