Exam Essentials

Explain when to implement fault tolerance.  Fault tolerance and disaster recovery must be implemented at some point and to some level on every network. Fault tolerance provides a means by which a computer or network has redundancy or the ability to recover from small faults and to continue providing services during the fault.

Explain when to implement disaster recovery.  Disaster recovery typically means a way of recovering after a major disaster, typically by backing up data on a regular basis, so that critical data is not lost.

Know what a full backup is, and explain the differences between the full, incremental, and differential backups.  Each backup type differs primarily in the amount backed up and whether the items being backed up have changed. Full backups typically back up the entire contents of a server, whether they’ve changed or not.

Know what an incremental backup is, and explain the differences between the full, incremental, and differential backups.  Each backup type differs primarily in the amount backed up and whether the items being backed up have changed. Incremental backups are usually used in conjunction with full backups and back up everything that has changed since the last backup (full or incremental).

Know what a differential backup is, and explain the differences between the full, incremental, and differential backups.  Each backup type differs primarily in the amount backed up and whether the items being backed up have changed. Differential backups are also used in conjunction with a full backup and back up everything that has changed since the last full backup.

Be able to describe why backups are important.  Backups are used to have a duplicate copy of any data so that in the case of hardware failure or data loss, the information can be obtained from the backup media.

Be able to describe different types of backup media.  The most common backup media include various forms of magnetic tape (DAT, Travan, DLT, etc.) and CD-ROM (CD-RW, DVD-ROM, etc.). Magnetic tape uses a plastic tape coated with metal oxide particles to store the data. It’s inexpensive, but has a finite life and relatively slow speed. CD-ROMs have a much longer life and higher speeds, but much smaller capacities.