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By Mistake on Ubuntu 9.04 my colleague has changed the permissions to 777 on root directory (/)

whats the best way to recover the permissions ?

marked as duplicate by Falcon Momot, Smudge, Ward, yagmoth555, Jenny D Apr 13 '16 at 16:01

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If he did not chmod -R the Directory Root - don't panic. Changing back the root directories permission to default can be achieved via:

chmod 755 / 
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    Double check it's owned by root:root as well. – Philip Reynolds Nov 10 '10 at 10:35
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    I've re-installed ubuntu !! now onwards I've to be careful for sudoers users !!! – necromancer Nov 10 '10 at 17:09

if it's recursive , you could mount a new ubuntu installation and make a script which compares default permissions for every file with yours. Of course it cannot work for files other than the basic installation. For the extra files you could reinstall the "world" (I borrow the term from gentoo, i don't how it's called in Ubuntu) {It's the file which says what packages are installed on your system}

  • for future reference, reinstalling world in ubuntu is apt-get --reinstall install $(dpkg --get-selections|grep install |grep -v deinstall|awk '{print $1}'), fuzzy memory but tested code – Behrooz Jul 26 '15 at 6:19

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