...
...also, it would be nice to see explanation 'what is this good for'.
Closest explanation I remember was 'it will protect you by making
system unbootable if someone stole disk with your /usr filesystem --
but not / filesystem -- added some rootkit, and then stealthily
returned it'. That seems a) very unlikely scenario and b) probably
better solved by encrypting /usr.
Pavel
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(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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