Imation - Backup Basics: Three Backup Plans

Getting started with a backup plan can seem difficult. It doesn't have to be: Building a successful backup plan is easy when you follow three key principles:

Back up every day, and perform a full backup at least once a week
Test your backup process (and your ability to restore) at least monthly or quarterly
Store one copy of your full backup off-site for security

Removable data storage media helps you create a moveable backup that can be transported off-site or protected away from your computers for increased security.

Choosing your media: Optical or tape?
Some people think they need to choose between optical (CD, DVD) technology or tape. Depending on the amount and type of data you need to back up, you may use either or both! Optical and tape media can be easily transported off-site and archived. If you use tape for your full backups, you may find that you can use optical media for your incremental backups as part of your tape backup program.

Choosing your plan
When choosing a backup plan for your business consider what risks you are willing to take with your data—in particular, what data is most critical and what level of loss you want to be prepared to face. A good rule of thumb is the more often you rotate your tapes, the safer your data is. If you use the same tape two days in a row, you may risk losing the prior day's files.

Think of the possible hazards your business could face. These can range from natural disasters—such as floods, fires, hurricanes or tornados—to terrorism, hackers or disgruntled employees.
Make a business decision on what level of recovery is required for your business.
a. Do you generate data daily that needs to be protected?
b. If your business is destroyed in a disaster, could you start up in a different location if you had your critical business data?
If appropriate, create a contingency plan to remain in operation if your office becomes unusable. Notify your employees of this plan and provide regular updates.

Each of these three backup regimens can be implemented with either tape or optical technologies. If you have more data than fits on a single cartridge or disc, you can multiply the amount of media needed to plan your budget and media inventory.

Some definitions that will help you understand these backup plans:

Incremental Backup — backup of all changes since last incremental backup, therefore, the first day follow your full backup will include the changes for that day. The second day’s incremental would only include changes that day.
Differential Backup — backup of all changes since last full backup. The day following the full backup would include changes that day. The differential backup for the second day following a full backup would include the changes the first day and the second day since the full backup.
Full Backup — backup of all files in your critical file set
On-site storage — Onsite storage of tapes should be far enough away from your system so that if you system is destroyed in an accident, your backup copy will not suffer the same fate. Fireproof safes are often a good option.
Off-site — Off-site storage of tapes should be a separate physical location (different office building, safe-deposit box, home storage, etc.).

Three Tape Backup

In a Three Tape Backup, you'll need one disc or tape for your daily incremental backup, and two discs or tapes for full weekly backups:

Disc/Tape 1 = Monday-Tuesday-Wednesday-Thursday backup of daily file changes. (Incremental Backup)
Disc/Tape 2 = Odd week Friday backup of all files, stored securely off-site (Full Backup)
Disc/Tape 3 = Even week Friday backup of all files, stored securely off-site(Full Backup)

Six Tape Backup

In a Six Tape Backup, you'll need four discs or tapes for your daily incremental backups, and two discs or tapes for full weekly backups:

Disc/Tape 1 = Monday backup of daily file changes. (Incremental Backup)
Disc/Tape 2 = Tuesday backup of daily file changes. (Incremental Backup)
Disc/Tape 3 = Wednesday backup of daily file changes. (Incremental Backup)
Disc/Tape 4 = Thursday backup of daily file changes. (Incremental Backup)
Disc/Tape 5 = Odd week Friday backup of all files, stored securely off-site (Full Backup)
Disc/Tape 6 = Even week Friday backup of all files, stored securely off-site. (Full Backup)

Ten Tape Backup

In a Ten Tape Backup, you'll need four discs or tapes for your daily incremental backups, three discs or tapes for weekly incremental backups, and three discs or tapes for full monthly backups:

Disc/Tape 1 = Monday backup of daily file changes. (Incremental Backup)
Disc/Tape 2 = Tuesday backup of daily file changes. (Incremental Backup)
Disc/Tape 3 = Wednesday backup of daily file changes. (Incremental Backup)
Disc/Tape 4 = Thursday backup of daily file changes. (Incremental Backup)
Disc/Tape 5, 6, 7 = Friday backup of weekly file changes stored securely off-site (Incremental Weekly Backup)
Disc/Tape 8, 9, 10 = Full backup on the fourth Friday of each month stored securely off-site (Full Monthly Backup)

One extra tape is used for an incremental backup if there is a fifth Friday in a month