FC0-U71 Security Practice Question

Which of the following is the best practice for backing up data according to the 3-2-1 rule?

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

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Three copies on two different media types, with one copy stored offsite

The 3-2-1 rule means at least three copies of data, on two different types of storage media, with one copy stored offsite.

Answer analysis

For each option: why learners choose it and why it is or isn't the right answer here.

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Three copies on two different media types, with one copy stored offsite
Why this is correct
The 3-2-1 rule demands three total copies, two distinct storage media, and one offsite. This option matches all three constraints exactly, ensuring resilience against local hardware failure, media-specific corruption, and site-wide disasters such as fire or flood.
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Three copies on three different external hard drives stored in the same building
Why it's wrong here
Keeping all three copies in one building satisfies the copy count but violates the off-site requirement, so a single fire, flood or theft destroys every backup. The 3-2-1 rule exists precisely to survive site-wide disasters; three drives in one room would only guard against individual disk failure.
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Two copies on the same server, one on a different server
Why it's wrong here
This gives three copies but only two media types and no off-site location, so a site-wide incident still destroys everything. The 3-2-1 rule requires one copy off-site; two copies on one server plus one elsewhere on the same network would only survive a single server failure.
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One copy on the same drive, one on an external drive, one in the cloud
Why it's wrong here
Keeping one copy on the same drive as the original means a drive failure destroys both source and backup, leaving only two surviving copies. The 3-2-1 rule requires three copies on two media with one off-site; co-locating a copy with the original defeats the purpose.

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