Unix Suppose you had to choose between the following two backup schemes: 1) Full

Question

Unix

Suppose you had to choose between the following two backup schemes:

1) Full backup on odd months (January, March, etc), Differential on even months (Febuary, April), and Incrementals backups once a week

2) Full backup every month, differentials on every other week, and incrementals every week in between. Answer the following questions:

What would be the difference in the number of tapes to have a 6 month archival window between the two approaches (assuming they are all the same tapes)? (Show your work)

Explanation / Answer

1) With full backup, all the files and folder are copied into the system each time when the full backup is scheduled. So if you perform a full backup on odd months like January, March etc., then entire files and folders copies are stored in the network on a particular date of odd months. This will increase the restoration faster and simpler but requires more time to back up the entire data. Whereas performing a differential backup on even months will require first full backup followed by backup on to all changes made between the data of first full backup and last full backup. Like if you have performed a First full backup on 1 January then the second full backup will be performed on 1 March and third on 1 May, the differential backup will then be performed between 1 January to 1 March and then from 1 January to 1 May. This backup requires less storage space comparative to Full backup but more than the incremental backup.

2) If the full backup is performed on the first Sunday of the month(January, February, etc., ) then the entire files and folder will then get stored into the system whenever the Full backup is performed. However, a differential backup is performed on Sunday of the month except the first one, then all the data differences will get stored in the system on every other week such as Sunday of the 1st week to the Sunday of the last week of the month. Which will require allows faster restoration time. Between Full back up conducted between every month and differential backup on every other week, an incremental backup will be performed every week in between and backup will be stored only with the changes made in their consecutive weeks like incremental backup between the first Sunday and second Sunday of the month, incremental backup between the second and the third Sunday of the month and so on.

From the above two approaches, the number of tapes requires performing backup will be more likely to be in the second approach.

Hope this explanation will be helpful for you.

Related Questions

Navigate

• Browse (All)
• Browse U
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.