Creating a Backup and Recovery Plan


Data backup is an insurance plan. Important files are accidentally deleted all the time. Mission-critical data can become corrupt. Natural disasters can leave your office in ruin. With a solid backup and recovery plan, you can recover from any of these. Without one, you're left with nothing to fall back on.

Figuring Out a Backup Plan

It takes time to create and implement a backup and recovery plan. You'll need to figure out what data needs to be backed up, how often the data should be backed up, and more. To help you create a plan, consider the following:

  • How important is the data on your systems?

    The importance of data can go a long way in helping you determine if you need to back it up ”as well as when and how it should be backed up. For critical data, such as a database, you'll want to have redundant backup sets that extend back for several backup periods. For less important data, such as daily user files, you won't need such an elaborate backup plan, but you'll need to back up the data regularly and ensure that the data can be recovered easily.

  • What type of information does the data contain?

    Data that doesn't seem important to you might be very important to someone else. Thus, the type of information the data contains can help you determine if you need to back up the data ”as well as when and how the data should be backed up.

  • How often does the data change?

    The frequency of change can affect your decision on how often the data should be backed up. For example, data that changes daily should be backed up daily.

  • Can you supplement backups with shadow copies?

    Shadow copies are point-in-time copies of documents in shared folders. These point-in-time copies make it easy to recover documents, as you can quickly go back to an older version in case a document is deleted or overwritten accidentally. You should use shadow copies in addition to standard backup ”and not to replace backup procedures.

  • How quickly do you need to recover the data?

    Time is an important factor in creating a backup plan. For critical systems, you might need to get back online swiftly. To do this, you might need to alter your backup plan.

  • Do you have the equipment to perform backups?

    You must have backup hardware to perform backups. To perform timely backups, you might need several backup devices and several sets of backup media. Backup hardware includes tape drives, optical drives, and removable disk drives. Generally, tape drives are less expensive but slower than other types of drives .

  • Who will be responsible for the backup and recovery plan?

    Ideally, someone should be a primary contact for the organization's backup and recovery plan. This person might also be responsible for performing the actual backup and recovery of data.

  • What's the best time to schedule backups?

    Scheduling backups when system use is as low as possible will speed the backup process. However, you can't always schedule backups for off-peak hours. So you need to carefully plan when key system data is backed up.

  • Do you need to store backups off-site?

    Storing copies of backup tapes off-site is essential to recovering your systems in the case of a natural disaster. In your off-site storage location, you should also include copies of the software you might need to install to reestablish operational systems.

The Basic Types of Backup

There are many techniques for backing up files. The techniques you use will depend on the type of data you're backing up, how convenient you want the recovery process to be, and more.

If you view the properties of a file or directory in Windows Explorer, you'll note an attribute called Archive. You often use this attribute to determine whether a file or directory should be backed up. If the attribute is on, the file or directory might need to be backed up. The basic types of backups you can perform include

  • Normal/full backups

    All files that have been selected are backed up, regardless of the archive attribute's setting. When a file is backed up, the archive attribute is cleared. If the file is later modified, this attribute is set, which indicates that the file needs to be backed up.

  • Copy backups

    All files that have been selected are backed up, regardless of the archive attribute's setting. Unlike a normal backup, the archive attribute on files isn't modified. This allows you to perform other types of backups on the files at a later date.

  • Differential backups

    Designed to create backup copies of files that have changed since the last normal backup. The presence of the archive attribute indicates that the file has been modified and only files with this attribute are backed up. However, the archive attribute on files isn't modified. This allows you to perform other types of backups on the files at a later date.

  • Incremental backups

    Designed to create backups of files that have changed since the most recent normal or incremental backup. The presence of the archive attribute indicates that the file has been modified and only files with this attribute are backed up. When a file is backed up, the archive attribute is cleared. If the file is later modified, this attribute is set, which indicates that the file needs to be backed up.

  • Daily backups

    Designed to back up files using the modification date on the file itself. If a file has been modified on the same day as the backup, the file will be backed up. This technique doesn't change the archive attributes of files.

In your backup plan you'll probably want to perform full backups on a weekly basis and supplement this with daily, differential, or incremental backups. You might also want to create an extended backup set for monthly and quarterly backups that includes additional files that aren't being backed up regularly.

Tip

You'll often find that weeks or months can go by before anyone notices that a file or data source is missing. This doesn't mean the file isn't important. Although some types of data aren't used often, they're still needed. So don't forget that you might also want to create extra sets of backups for monthly or quarterly periods, or both, to ensure that you can recover historical data over time.


In previous editions of the Backup utility for Windows, Backup would write errors to the log for any files that were in read+write or write mode. Files in these modes are in use. In Windows Server 2003, Backup uses the Shadow Copy feature to create automatic point-in-time backups of files that are in use. As an administrator, you probably know how frustrating it can be to try to get a complete backup set, and this feature goes a long way toward ensuring that the Backup utility is a viable option for backing up data in a wide variety of conditions.

Differential and Incremental Backups

The difference between differential and incremental backups is extremely important. To understand the distinction between them, examine Table 15-1. As it shows, with differential backups you back up all the files that have changed since the last full backup (which means that the size of the differential backup grows over time). With incremental backups , you back up only files that have changed since the most recent full or incremental backup (which means the size of the incremental backup is usually much smaller than a full backup).

Table 15-1. Incremental and Differential Backup Techniques

Day of Week

Weekly Full Backup with Daily Differential Backup

Weekly Full Backup with Daily Incremental Backup

Sunday

A full backup is performed.

A full backup is performed.

Monday

A differential backup contains all changes since Sunday.

An incremental backup contains changes since Sunday.

Tuesday

A differential backup contains all changes since Sunday.

An incremental backup contains changes since Monday.

Wednesday

A differential backup contains all changes since Sunday.

An incremental backup contains changes since Tuesday.

Thursday

A differential backup contains all changes since Sunday.

An incremental backup contains changes since Wednesday.

Friday

A differential backup contains all changes since Sunday.

An incremental backup contains changes since Thursday.

Saturday

A differential backup contains all changes since Sunday.

An incremental backup contains changes since Friday.

Once you determine what data you're going to back up and how often, you can select backup devices and media that support these choices. These are covered in the next section.



Microsoft Windows Server 2003 Administrator[ap]s Pocket Consultant
Microsoft Windows Server 2003 Administrator[ap]s Pocket Consultant
ISBN: 735622450
EAN: N/A
Year: 2003
Pages: 141

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