Password-protected single-user mode on RHEL/CentOS/5.x/6.x

Password-protected single-user mode on RHEL/CentOS/5.x/6.x

Hello everyone, if you have not used a password to protect the single-user mode, this poses a great risk to your Linux server. Therefore, when it comes to security, it is very important to use a password to protect the single-user mode.

This article will show you how to use a password to protect your single-user mode on RHEL/CentOS 5.x and RHEL/CentOS 6. x.

Please execute the given command carefully, otherwise your system will not be able to start normally. First, I will ask you to finish reading and then try. Please bear the relevant consequences by yourself :-)

Password Protect

1. Before starting RHEL/CentOS 5. x1.1, back up your/etc/inittab

1. Cp/etc/inittab. backup

To protect the password in single-user mode, run the following command with root :-

1. [Root @ tejas-barot-linux ~] # Sed-I '1i su: S: wait:/sbin/sulogin '/etc/inittab

In this way, you will see

1. Su: S: wait:/sbin/sulogin
2. # Default runlevel. The runlevels used by RHS are:
3. #0-halt (Do NOT set initdefault to this)
4. #1-Single user mode
5. #2-Multiuser, without NFS (The same as 3, if you do not have networking)
6. #3-Full multiuser mode
7. #4-unused
8. #5-X11
9. #6-reboot (Do NOT set initdefault to this)
10. #
11. Id: 3: initdefault:

NOTE: If you do not want to use the sed command, you can add "su: S: wait:/sbin/sulogin" to the top of the/etc/inittab"

2. Before starting RHEL/CentOS 6. x2.1, back up your/etc/inittab

1. Cp/etc/sysconfig/init. backup

2.2 To protect the single-user mode with a password, run the following command with root :-

1. [Root @ tejas-barot-linux ~] # Sed-I's/SINGLE =\/ sbin \/sushell/SINGLE =\/ sbin \/sulogin/'/etc/sysconfig/init

In this way, you will see

1. SINGLE =/sbin/sulogin

Note:-If you do not want to use sed, you can directly change it to "SINGLE =/sbin/sysconfig/init" in/etc/sysconfig/init"

Enjoy Linux :) Enjoy open source