Linux is a multi-user operating system. To use the system, users must first log in to the system. After using the system, they must log out of the system.
When a user logs in to the system, in order for the system to recognize him/herself, he or she must enter the user name and password, which must be verified by the system before they can enter the system. Two accounts can be created during the system installation process: (Recommended learning: linux operation and maintenance)
1. root--super user account. Use this account to log in to the system do anything.
2. Ordinary users--This account is for ordinary users and can perform limited operations.
General Linux users are ordinary users, and system administrators generally use superuser accounts to complete some system management tasks. If you only need to complete some tasks that can be completed by a normal account, it is recommended not to use a superuser account to avoid inadvertently damaging the system.
User login is carried out in two steps:
In the first step, enter the user’s login name, and the system will identify the user based on the login name;
The second step is to enter the user's password. This password is a string of characters chosen by the user. It is confidential to other users and is a keyword used by the system to identify real and fake users when logging in.
In a Linux system, the system administrator assigns the user a username and an initial password when creating a new account for the user. In addition, the Linux system assigns a host name to the computer.
The host name is used to identify an independent computer on the network (even if the user's computer is not connected to the Internet, it should have a host name). The default host name given by the Linux system is: localhost. In the examples below, we assume the username is "wah" and the system's hostname is "localhost".
Super user login;
The super user’s user name is root, and the password has been set when installing the system. After the system starts successfully, the screen displays the following prompt:
localhost login:
At this time, enter the super user name "root", and then type the Enter key. At this time, the user will see a prompt to enter the password on the screen:
localhost login:root Password:
At this time, the password needs to be entered. The password will not be displayed on the screen when you enter it. If the user enters an incorrect password, they will see the following message on the screen:
login incorrect.
You will need to re-enter it. When the user correctly enters the user name and password, he can legally enter the system. The screen displays:
[root@loclhost ~] #
This indicates that the user has logged in to the system and can perform operations. Here "#" is the system prompt of the super user.
Normal user login
Normal user login After establishing a normal user account, you can log in.
When logging in, the user will see a prompt similar to the following on the screen:
localhost login:
At this time, enter the user name "wah" and then type the Enter key. At this time, the user will see a prompt to enter the password on the screen:
localhost login:wah Password:
At this time, the password needs to be entered. The password will not be displayed on the screen when you enter it. If the user enters an incorrect password, they will see the following message on the screen:
login incorrect.
You will need to re-enter it. When the user correctly enters the user name and password, he can legally enter the system. The screen displays:
[wah@loclhost wah] $
This indicates that the user has logged in to the system and can perform operations.
The above is the detailed content of How to log in on linux. For more information, please follow other related articles on the PHP Chinese website!

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