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sysadmin and root/superuser

summary

    This subchapter looks at system administration and the root or superuser account.

    As we look at more advanced features and commands, we need to become aware of the root or superuser account and capabilities and how to safely access that power.

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Teach Yourself UNIX/Linux System Administration and Shell Programming

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sysadmin and root/superuser

    This subchapter looks at system administration and the root or superuser account.

sysadmin

    In the UNIX world, the system administrator is often called the sysadmin.

root/superuser

    The root or superuser account has total authority to do anything on the system. This power is great for fixing problems, but bad because one accidenttally mistyped character could be very destructive. Some systems also have admin accounts of similar power.

    Because of the potential for destructiveness, system administrators typically login with either a normal user account or a limited admin account for every day work and then switch to superuser or root only when absolutely necessary (and then immediately switch back).

    The UNIX command for temporarily switching to root or superuser power is the sudo command, discussed in the next subchapter.

special powers

    The root or superuser account has powers that “mere mortal” accounts don’t have.

    The root account has access to commands that effect the entire computer or system, such as the ability to halt or shutdown the system.

    The root account is not affected by read and write file access permissions. The root or superuser account can create, remove, read, or write any file anywhere on the system.

    Some commands have built-in restrictions that the root or superuser can ignore. For example, the system administrator can change any user’s password without knowing the old password.


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    View music player in action: www.musicinpublic.com/.

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free book on UNIX/Linux System Administration

Teach Yourself UNIX/Linux System Administration and Shell Programming

free computer programming text book project

Building a free downloadable text book on computer programming for university, college, community college, and high school classes in computer programming.

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    †UNIX used as a generic term unless specifically used as a trademark (such as in the phrase “UNIX certified”). UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Ltd.

    Names and logos of various OSs are trademarks of their respective owners.

    Copyright © 2012 Milo

    Created: July 5, 2012

    Last Updated: August 24, 2012


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