How to change and reset forgotten root password in RHEL 9

In the installation RHEL 9 when , Installation process ​​ The preface suggests that we choose a complex password , Although the password is complex enough , But the probability of forgetting the password is very high . When your users are not even added to wheel Group time , Things will get more complicated .

This tutorial will guide you on how to 3 In this case, change the forgotten root password , We are sure that you will be able to recover your forgotten password at the end of this guide .

Method 1： stay RHEL 9 Change in root password

therefore , If you are root The user also wants to change the existing root password , You can use a single command to complete this task .

# passwd

It will ask you to enter a new root password . In order to confirm , It will ask you to enter your new password again , And will throw a message “ All authentication tokens have been successfully updated ”.

Method 2： With Sudo User changes Root password

For most people , This will be the user added to wheel Group and want to change root Password situation . thankfully , Even if you don't know your current password , You can also change your root password .

Add users to wheel Group

# usermod -aG wheel tecmint

I want to send your root Password changed to wheel Group users , Please use the given command ：

$ sudo passwd root

First , Will be asked to enter your user password , then , You will be allowed to change your root password .

Method 3： stay RHEL 9 Change forgotten root password

This method is applicable to non root User or local user is not added to Wheel Group , But I still want to change or reset the forgotten root Password users .

This is the most complicated method , When using this method , Make sure to read the command twice before applying it , Because we will deal with GRUB.

The first 1 Step ： Get into GRUB Edit mode

To get into GRUB Edit mode , First , We have to restart the system . When you see GRUB 2 On screen , Press 'e' Key interrupt boot process .

Once you press 'e', It will show us the kernel startup parameters .

step 2： Edit kernel boot parameters

Enter the kernel boot parameters , Go to linux At the end of the first line . The easiest way is to first find out with linux The first line , Then press CTRL + e Jump to the end of this line .

After reaching the end of the line , add to rd.break And press CTRL + x Start the system with the changed parameters .

The first 3 Step ： Reset forgotten Root password

You will receive an emergency mode prompt . So let's start here , We will install our drive , Get into chroot Environmental Science , And change our root password . Press Enter key , Will appear sh-5.1 Prompt for further processing .

By default , The file system is mounted in read-only mode /sysroot Under the table of contents . By using the given command , We will remount them so that they can write and change our password .

# mount -o remount,rw /sysroot

After mounting the drive , Let's get into chroot Environmental Science , This will allow us to make changes to the system files directly .

# chroot /sysroot

Last , We can use the given command to change our root password ：

After changing the password , Let's enable it the next time the system boots SELinux Relabel the process .

# touch /.autorelabel

Important note ： We don't run any scripts here , So please make sure you /.autorelabel Use... Correctly .

After changing the password and relabeling , Let's exit with the given command chroot Environmental Science ：

# exit

Again , To exit sh-5.1 Prompt , We will use the given command ：

# exit

The first 4 Step ： verification Root password

To verify that we have successfully changed root password , Please log in as an ordinary user, open the terminal simulator and root Run interactive as shell , Use the given command ：

$ su

Enter the newly configured root password . To print with the current user ID Associated user name , Use the following command ：

# whoami

It will act as “ root ” return .

This guide shows 3 Methods , You can use these methods to change your RHEL 9 Forgotten in root password .