Basics For RHCSA (1)

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Linux app finder :

When we think to migrate to the linux from windows, we have to find the alternative applications which match to our purpose. For that we use Linux app finder. 

Linux Distrowatch :

This website is used to know about all the linux distribution.

So when we come to the terminal. There are many things to identify.


Managing User accounts

There are two main types of users.
  1. System Users
  2. Regular Users

System Users :

These users are automatically added to the system by the system and they are used to maintain the system and support for the system. They can run the system process. For an example shutdown is a system user.

Regular Users :

These users are added to the system by the user (manually added).

So there are some specific user ids for users. 

  • uid 0 --------------- for Super user / root
  • uid 1 - 200 -------- for System users
  • uid 201 - 999 ----- for System users
  • uid 1000 + -------- for Regular users 

 

Special File paths 

  • /etc/passwd --------------- User information
  • /etc/shadow --------------- User Password Information
  • /etc/group ----------------- Group entries 
  • /etc/login.defs ------------ User account parameters such as group ids , user ids etc. 
  • /etc/shells ----------------- Available shells
  • /etc/hostname ------------ Hostname
  • /proc/partitions ----------- Partitions information in hard disk 
This may help you later in this course.

Cat command


Simply this a command which is used to see what is the content of the file or given file path without opening any text editor.





What is BASH  ?

Bourne Again Shell (bash) is a interpreter which is used to run shell commands. It uses bash language.


Basics for RHCSA(2) is containing basic commands and about "how to create own commands".



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