Your organization has a 24-hour recovery point objective for a file server and implements a backup strategy with the most negligible overhead and the best efficiency in terms of restoration. If it conducts full backup at 00:00 AM every Sunday, which of the following is most likely to be restored once a storage failure happens at 10:00 AM on Wednesday? (Wentz QOTD)
A. The Wednesday full backup set only
B. The Sunday full backup set and one differential backup set
C. The Sunday full backup set and three incremental backup sets
D. Both before and after images (BFIM and AFIM)
Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.
My suggested answer is A. The Wednesday full backup set only.
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The full backup strategy conducts full backup every day. When restoring data, what we have to do is to restore the full backup set. It has the most negligible overhead and the best efficiency in terms of restoration.
If we take the differential backup strategy, the full backup set on Sunday must be restored first, then the Wednesday differential backup set.
If we take the incremental backup strategy, the full backup set on Sunday must be restored first, then the Monday, Tuesday, and Wednesday differential backup sets.
您的組織為檔案伺服器製定了 24 小時恢復點目標(RPO)，並實施了額外負擔(overhead)最小且回存(restore)效率最高的備份策略。 如果每週日上午 00:00 進行完整備份，那麼一旦週三上午 10:00 發生存儲故障，以下哪項最有可能被回存？ (Wentz QOTD)
D. 前後圖像（BFIM 和 AFIM）