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- All right.

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Next task is to create the
file /tmp/protectedfile,

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containing the text, I am protected.

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And ensure that this file can
be added to, but not removed,

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and current contents cannot be changed.

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So the solution is obviously
in attributes, man chattr.

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And what we need is the
attribute a for append only.

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So let me create /tmp/protectedfile.

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And in there, the text, I am protected.

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If you see questions
like this on the exam,

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make sure you don't make any typos

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because if they want you
to have a text in there,

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then really they are going to check for it

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and you'll lose points if you have a typo.

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So that was easy.

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And the other part also
is not very complicated.

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Chattr +a on /tmp/protectedfile.

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Lsattr on /tmp/protectedfile
is showing you that this works.

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00:01:15,570 --> 00:01:20,570
Let's do echo hello >>
/tmp/protectedfile, which is working.

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Let's use rm -f on /tmp/protectedfile,
which is not allowed.

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So protectedfiles, append only.

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It's a useful attribute.

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Not as commonly known as immutable,

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but definitely very useful as well.