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- In this video you'll learn
about filesystem attributes.

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So the POSIX standard defines
a number of attributes

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that can be used to add security to files.

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You can use chattr to set them,

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and lsattr to get an overview

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of currently applied attributes.

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There is a couple of
attributes that is defined,

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but the immutable
attribute is most common.

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Let me show you.

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So I'm creating a file
with the name removeme.txt,

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and then chattr +i on removeme.txt.

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Now what is going to happen

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if they use rm -f on removeme.txt?

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I'm getting an operation not permitted.

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But I am root, yes that is right,

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but lsattr on removeme

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is showing that the
immutable attribute is set,

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and if an attribute is
set, even if you are root,

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you can't remove it without
first removing the attribute.

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And that's what I'm doing next,

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chattr -i on removeme.txt,
and now it's gone,

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and now I should be
able to remove the file.

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There we go, and now it's gone.

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That is how you can use attributes.

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This is pretty convenient

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if you want to add some
protection to files,

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and you wanna make sure nobody
by accident is removing them.

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Now if you have a look at
the man page, man chattr,

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then you can see all the
letters that can be used

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for the attributes right here.

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But as I was telling you,

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many of these attributes are
not really very well supported.