Skip to main content

Root login

  1. Root Login:

    • User: The "root" user is the superuser or system administrator in a Linux system. It has full access and control over the entire system.
    • Login: Root login refers to the act of logging into a Linux system using the root user's credentials (username and password).
    • Privileges: When logged in as root, you have unrestricted access to system files, directories, and settings. You can execute any command, modify any file, and make system-wide changes. Root privileges should be used with caution, as they can potentially harm the system if misused.

    Example of Root Login:

    # To log in as the root user
    su -

The User Identifier (UID) of the root user, which is used to uniquely identify the root user in a Linux or Unix-based system, is traditionally set to 0. In most systems, the root user's UID is 0 by default. The UID is stored in the system's user account database, typically in the "/etc/passwd" file. Here is an example entry for the root user in the "/etc/passwd" file:

root:x:0:0:root:/root:/bin/bash

In this entry, the UID is set to 0, and the root user is associated with the username "root." The root user's home directory is "/root," and the default shell is "/bin/bash."

  1. Root User:

    • "Root" is the specific username of the superuser in these systems.
    • The root user has the highest level of access and control over the entire system.
    • The root user's home directory is typically "/root."
    • Access to the root user account is achieved by logging in directly as "root" or by using the "su" (switch user) command.

  2. Superuser:

    • "Superuser" is a more general term that refers to any user account with elevated privileges, not necessarily named "root."
    • Superuser accounts, other than "root," can be created on the system, and they can be granted administrative privileges.
    • These superuser accounts are typically added to the "sudoers" file, which defines which users are allowed to use the "sudo" command to execute commands with superuser privileges.
    • Superuser accounts can have different usernames, and they may have their own home directories.

So, while "root" refers specifically to the default and most powerful superuser account in Linux and Unix, "superuser" is a broader term that can apply to any account with elevated privileges. In practice, "superuser" accounts other than "root" are often created to delegate administrative tasks to specific users while maintaining accountability and traceability through the use of the "sudo" command.