Linux for Troubleshooting - sudo

Sudo :

1. Root user - Critical operations are taken care.
2. sudo or su do
3. root binary setuid
4. /etc/sudoers - default sudo security policy pulgin - this file defines who can run what .

Why we need sudo ?

Risk - to avoid normal user changing the configurations.
Think before you type.

sudo su --> changes to root in the terminal --> sudo useradd techie

1. Lets give this user a root access
2. Important file is /etc/sudoers

1. sudo is more secure than su command.
2. /var/log/secure or /var/log/auth.log --> logs that store sud usage.
3. Below one shows the logs in auth .

Another important file is /etc/passwd

Once the user is getting created , it stores the data in the passwd file with password . If there is not password then ' x ' won't be there. (TBD)

Installing Programs :

1. rpm - Package Manager or apt in some distro.
2. Package Management System.
3. .rpm - file format
4. Yellowdog Updater or Modified Yum - Library - Utility

su command :

1. command for the user
2. Below user as root access .

Note :

1. what is the meaning of this ? export VISUAL=vim; visudo (TBD)
2. userdel for deleting the user also we can use 'f' to force the deletion. i.e., userdel -f Tom While deleting if the user is running some process we can use 'f' to force them.