Data Backup


 

Purpose 

Backing up your data is your insurance policy in the event of disaster recovery.  A backup schedule is an essential part of any data protection strategy.  Your backup system should be designed specifically for your system and the type of data on it.  The overall requirement of any backup plan is that it is able to restore all the data on your system within an acceptable time.

Frequency

The frequency and type of backup will depend on your system and the type of data supported on it.  If your system supports a large ongoing development project for instance, then the files are likely to change frequently and will need to be backed up at least daily and probably after hours.  On the other hand if the only volatile file on your system is a large database then its filesystem may need to be backed up several times a day, while other filesystems on the same system may only need to be backed up weekly

Storage Location

Backups  should be well labeled and stored in a cool, dry, dark place which is designated for backups so it is easy to find the right one when needed.  Your backups should be protected from theft, vandalism, and environmental disasters in a locked, environmentally controlled, fireproof location and possibly even off site for the ultimate backup storage.

Types of Backup Method

Full Backups - All of the files within a predefined set are copied to the backup media and they are marked as backed up.  The archive attribute is cleared for a file whenever it is modified.

Copy Only Backups - All of the files in a set a copied but none are marked as backed up. 

Differential Backups - All of the files in a set that have been modified since the most recent full backup are copied but not marked as backed up.

Incremental Backups - All the files in the set that have been modified since the most recent backup of any kind are copied and marked as backed up.

Daily Backups - All files in the set that were modified today are backed up, but none are marked as archived.

 

Type of Backup Methods 

Tape Backup

Type of Tape backup

    Travan

   DAT DDS#3

   8mm "Exabite"

   QIC

   DLT- Digital Linear Tape

Spanning Tapes

Spanning is where more than one tape is used for a large HDD - Try to avoid Spanning if possible.                             

Time to keep tapes

3 months - Date the tapes

Maintenance - check tapes physically look at the tapes - look for signs of damage

Do not place tapes near - speakers, monitors, heat or moisture                                                                                       

Software

Compression

        When to use compression

                Files take longer to backup and restore when compressed