How to change the root password and retrieve the password in Linux

Log on as a root user and run the following command: # passwd username (change password) # useradd username (add user): [root @ bogon ~] # PasswdrootChangingpasswordforuserroot.

Log in as root and execute:

# Passwd user name (change password)

# Useradd user name (add user)

Example: [root @ bogon ~] # Passwd root

Changing password for user root.

New UNIX password:

Bad password: it is based on a dictionary word

Retype new UNIX password:

Passwd: all authentication tokens updated successfully.

How to retrieve the root password in linux

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Linux root has the highest power. Once the root password is forgotten or stolen, it is a headache. how can I retrieve the root password? I will summarize it as follows:

(1) Linux system password cracking

1. press e in the grub option menu to enter the editing mode.

2. edit the line/init 1 (or/single) of the kernel)

3. Press B to restart

4. run the following command

Root @ # passwd root (configure the root password)

Enter new unix password: Enter a new password

Root @ # init 6

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(2) debian linux system password cracking

1. in the grub option menu 'debian GNU/Linux,... (recovery mode) ', press e to enter the editing mode.

2. edit the ro single line in the kernel to rw single init =/bin/bash, and press B to restart.

3. run the following command

Root @ (none) # mount-

Root @ (none) # passwd root

Root @ (none) # reboot

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(3) Freebsd system password cracking

1. boot to enter the boot menu

2. select each item (press 4) to enter the single-user mode.

3. enter a command column.

Root @ # mount-

Root @ # fsck-y

Root @ # passwd (password change command)