| Windows XP Backup provides five backup types that | | | | neither looks for nor clears markers. If you want to |
| define what data is backed up, such as only files that | | | | back up all files and folders that change during the |
| have changed since the last backup. | | | | day, use a daily backup. |
| Some backup types use backup markers, also known | | | | Combining Backup Types |
| as archive attributes, which mark a file as having | | | | An effective backup strategy is likely to combine |
| changed. When a file changes, an attribute is set on | | | | different backup types. Some backup types require |
| the file that indicates that the file has changed since | | | | more time to back up data but less time to restore |
| the last backup. When you back up the file, this | | | | data. Conversely, other backup types require less |
| clears or resets the attribute. | | | | time to back up data but more time, to restore data. |
| Normal | | | | If you combine backup types, markers are critical. |
| During a normal backup, all selected files and folders | | | | Incremental and differential back?up types check for |
| are backed up. A normal backup does not rely on | | | | and rely on the markers. The following are some |
| markers to determine which files to back up. During a | | | | examples of combining different backup types: |
| normal backup any existing marks are cleared and | | | | Normal and differential backups. On Monday a normal |
| each file is marked as having been backed up. Normal | | | | backup is performed and on Tuesday through Friday |
| backups speed up the restore process because the | | | | differential backups are performed, Differential |
| backup files are the most current and you do not | | | | backups do not clear markers, which means that |
| need to restore multiple backup jobs. | | | | each backup includes all changes since Monday. If |
| Copy | | | | data becomes corrupt on Friday, you only need to |
| During a copy back?up, all selected files and folders | | | | restore the normal backup from Monday and the |
| are backed up. It neither looks for nor clears markers. | | | | differential backup from Thursday This strategy |
| If you do not want to clear markers and affect | | | | takes more time to back up but less time to restore. |
| other backup types, use copy. For example, use a | | | | Normal and incremental backups. On Monday a normal |
| copy backup between a normal and an incremental | | | | backup is performed and on Tuesday through Friday |
| backup to create an archival snapshot of network | | | | incremental backups are performed. Incremental |
| data. | | | | backups clear markers, which means that each |
| Differential | | | | back?up includes only the files that changed since the |
| During a differential backup, only selected files and | | | | previous backup. If data becomes corrupt on Friday, |
| folders that have a marker are backed up. It does | | | | you need to restore the normal back?up from |
| not clear markers. Because a differential backup does | | | | Monday and all incremental backups, from Tuesday |
| not clear markers, if you did two differential backups | | | | through Friday. This strategy takes less time to back |
| in a row on a file and nothing changed in the file, the | | | | up but more time to restore. |
| entire file would be backed up each time. | | | | Normal, differential, and copy backups. This strategy |
| Incremental | | | | is the same as the first example that used normal |
| During an incremental backup, only selected files and | | | | and incremental backups except that on Wednesday |
| folders that have a marker are backed up. It clears | | | | you perform a copy backup. Copy backups include all |
| markers. Because an incremental backup clears | | | | selected files and do not clear markers or interrupt |
| markers, if you did two incremental backups in a row | | | | the usual backup schedule. Therefore, each |
| on a File and nothing changed in the file, the file | | | | differential backup includes all changes since Monday. |
| would not be backed up the second time. | | | | The copy backup type done on Wednesday is not |
| Daily | | | | part of the Friday restore. Copy backups are helpful |
| During a daily backup, all selected files and folders | | | | when you need to create a snapshot of your data. |
| that have changed during the day are backed up. It | | | | |