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I would like to cleanly shut my system down but the response from 'shutdown -P now' is that I need to be logged in as root. I installed the 'root' command but I get an error message that 'root: cannot figure out DISPLAY, set it manually'. Since this didn't work I tried logging in as root (user name) and I realize I don't know the password. So I have two questions. One, on initial installation what does the root password become? Two, what do I do about the DISPLAY problem?

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First of all: you don't have to know the root's password, use your own with sudo command. For shutdown: sudo shutdown -P now, for example.

If you need a password for root, then issue:
1. sudo su
2. passwd root, and change the password.

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Thank you. What is the DISPLAY problem telling me? – Kevin Burton Oct 31 '12 at 15:53
ROOT is a C interpreter used for data analysis in particle physics. It was looking for a remote xclient and couldn't find one, so you would have to set the display to your machine manually (via a config file preferably) to use ROOT locally. – astex Oct 31 '12 at 17:09
Sorry I thought 'root' was a command to run other commands as the admin (like su). – Kevin Burton Oct 31 '12 at 19:41

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