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Glenn Norman

Glenn Norman

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Glenn Norman
Posted on July 20, 2018May 29, 2020 by Glenn

User Information

  1. Using the Linux Command Line
  2. The Linux Directory Tree
  3. Linux Shells and Basic Commands
  4. Changing Passwords
  5. Your Home Directory
  6. User Information
  7. Linux User Default Files
  8. Linux User Profiles and Paths
  9. sudo and su –
  10. Listing Files and Going Deep Into Filesystems
  11. Linux: Creating and Deleting Directories and Files

Where user information is stored

User names and primary groups are stored in /etc/passwd. To see this file:

cat /etc/passwd

This file can be directly edited, although this is not recommended. The format of each line is:

User name (normally all lower case)

Password (encrypted – only contains the letter ‘x’)

User ID (UID) (a unique number for each user)

Primary Group ID (GID)

Comment or “GECOS” (Often the person’s full name)

Home directory (normally /home/<user name>)

Default shell (normally /bin/bash)

Each field is separated by a colon.

Where passwords are stored

Passwords for each user are stored in /etc/shadow (assuming password shadowing has been implemented, which it almost always is). This file should only be changed using the useradd, usermod, or passwd commands.

Try this to see the MD5 or SHA hashed passwords:

cat /etc/shadow

 

CategoriesLinux Command Line, bash Scripting and Beginning Python TagsLinux, user profile

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  • [ GNU/Linux and Unix ]
  • [ Apache ]
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  • [ Python ]
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