Linux How to reset a root password on Fedora

A system administrator can easily reset a password for a user that has forgotten their password. But what happens if the system administrator forgets the root password? This guide will show you how to reset a lost or forgotten root password. Note that to reset the root password, you need to have physical access to the machine in order to reboot and to access GRUB settings. Additionally, if the system is encrypted, you will also need to know the LUKS passphrase.

Edit the GRUB settings

First you need to interrupt the boot process. So you’ll need to turn on the system or restart, if it’s already powered on. The first step is tricky because the grub menu tends to flash by very quickly on the screen.

Press E on your keyboard when you see the GRUB menu:

After pressing ‘e’ the following screen is shown:

Use your arrow keys to move the the linux16 line.

Using your del key or backspace key, remove rhgb quiet and replace with the following.

rd.break enforcing=0

After editing the lines, Press Ctrl-x to start the system. If the system is encrypted, you will be prompted for the LUKS passphase here.

Note: Setting enforcing=0, avoids performing a complete system SELinux relabeling. Once the system is rebooted,  restore the correct SELinux context for the /etc/shadow file. (this is explained a little further in this process)

Mounting the filesystem

The system will now be in emergency mode. Remount the hard drive with read-write access:

# mount –o remount,rw /sysroot

Password Change

Run chroot to access the system.

# chroot /sysroot

You can now change the root password.

# passwd

Type the new root password twice when prompted. If you are successful, you should see a message that all authentication tokens updated successfully.

Type exit, twice to reboot the system.

Log in as root and restore the SELinux label to the /etc/shadow file.

# restorecon -v /etc/shadow

Turn SELinux back to enforcing mode.

# setenforce 1
0 (0)
Article Rating (No Votes)
Rate this article
Attachments
There are no attachments for this article.
Comments
There are no comments for this article. Be the first to post a comment.
Full Name
Email Address
Security Code Security Code
Related Articles RSS Feed
Creating SWAP partition using FDISK & FALLOCATE commands
Viewed 896 times since Thu, Jan 16, 2020
RHEL: GPT/MBR partition tables (using disks larger than 2 TiB)
Viewed 10295 times since Sun, May 27, 2018
RHEL : How to deal with “CLOSE_WAIT” and “TIME_WAIT” connection
Viewed 13639 times since Thu, Feb 14, 2019
Setting up encrypted tunnel using stunnel
Viewed 1055 times since Fri, Sep 28, 2018
RHCS6: Create a new Logical Volume / Global Filesystem 2 (GFS2)
Viewed 1109 times since Sun, Jun 3, 2018
OEL 7 – How to disable IPv6 on Oracle Linux 7 – Follow Up
Viewed 7696 times since Wed, Jul 25, 2018
Jak znaleźć najszybszy publiczny serwer DNS w Polsce?
Viewed 1508 times since Mon, May 21, 2018
Build a simple RPM that packages a single file
Viewed 5429 times since Sat, Jun 2, 2018
awk printf
Viewed 11388 times since Wed, Aug 19, 2020
Tcpdump Examples Linux
Viewed 4053 times since Fri, Nov 16, 2018