incremental/differential backup??

gsrdrver7

Read about this in my net + book and the tech notes on this website as well. I still can't understand the difference between the two.

janmike

If you make an incremental backup, you are backing up everything changed since that last backup and the backup program changes the archive bit to indicate that the file has been backed up(or, if you would, to indicate that it hasn't changed since the last backup--last backup being the incremental backup you just made).

If you make a differential backup, you are backing up everything that has changed since the last full backup but the backup program does not change the archive bit(or, if you would, the archive bit still indicates that the file changed but hasn't been backed up yet since the last full backup).

Generally incremental backups are made on a daily basis to supplement the last full backup. If you need to restore files you have to run the last full backup plus every incremental backup to the time you lost the files. Incremental backups reduce backup time.

Differential backups can be made on a daily backup, but the length of time it takes to make the backup will increase daily because it's backing up everything changed since the last full backup. However, if you have to restore you only need the last full backup plus the most recent differential backup since it has a backup of everything changed since the last full backup. This is generally a quicker restoration method even though the daily differential backup takes longer than the daily incremental method.

Hope this helps. I think that this is something you almost have to drill yourself on until it sticks in your mind.