Backup and Recovery

Backup and Recovery

1. What is a backup?

   • Means to take copies of data so that if the system fails you can recover and continue to process the data without loss.
   • Involves the creation of copies of data and programs so that if the data or programs are damaged or lost they can be recreated from the backup copies.

2. Threats to data

   • Hardware failure
   • Damage
   • Theft
   • Hacking
   • Fire
   • Terrorist Attack
   • Natural Disaster

3. Types of backup

   • Full
     • Copy all your data.
     • Usually at the end of the day.
     • Takes a long time.
   • Incremental
     • Only backup changed files.
     • Slower to restore.
   • Differential
     • Only backup changed files from last full backup.
     • Ignores all previous non-full backups.
   • Real-Time Backup
     • Instant backup
     • Expensive

4. Storage Devices

   • Magnetic Tape
   • Hard Disks
   • Optical Disks
   • Remote backup service
   • Flash Memory