How To Reset root Password on CentOS 7
0 likes34,376 views
This document provides steps to reset the root password on RHEL 7 if it is forgotten: 1. Reboot the server and choose the "Core" kernel entry in the boot menu. 2. Edit the kernel entry to add "rw init=/sysroot/bin/sh" which will start the system in single user mode. 3. Run the "chroot /sysroot" command and then "passwd root" to set a new root password. 4. Run "touch /.autorelabel" and reboot to relabel the filesystem for SELinux.
How To Reset root Password on CentOS 7
- 1. How To Reset Root Password on RHEL 7 i | P a g e Table of Contents Overview.......................................................................................................................................................1 Applies To......................................................................................................................................................1 Pre-requisites................................................................................................................................................1 Choose Kernel - Core.................................................................................................................................1 Find Kernel Entry – ro ...............................................................................................................................2 Modify Kernel Entry – init.........................................................................................................................2 Change Root – sysroot..............................................................................................................................3 Set – Root Password .................................................................................................................................4 Relebal Filesystem – SELinux ....................................................................................................................4
- 2. How To Reset Root Password on RHEL 7 1 | P a g e Overview If you happen to forgot root password of the server. You have to login to the server with single user and edit the kernel entry and boot and change the root password. Applies To CentOS 7, RHEL 7; Tested on CentOS 7 Pre-requisites Console Access to the system. Choose Kernel Entry - Core In order to reset the root password, you need to reboot the server and choose “Core” kernel entry in the “boot” menu option. When the boot menu is shown; choose the kernel entry as below and press key “e” as shown below. CentOS Linux (3.10.0-229.11.1.el7.x86_64) 7 (Core) Note: Boot screen will be shown only for 5 seconds.
- 3. How To Reset Root Password on RHEL 7 2 | P a g e Find Kernel Entry – ro In the “Edit Kernel” option, navigate till you find text “ro” after root device mapper. Modify Kernel Entry – init Next, you need to modify the kernel entry as below; which will instruct the kernel to start into “sh”. rw init=/sysroot/bin/sh After modifying, press “Ctrl + x”, kernel will be instructed to start in single user mode.
- 4. How To Reset Root Password on RHEL 7 3 | P a g e Change Root – sysroot Execute chroot command or interactive shell with special root directory. Run the command as below; chroot /sysroot
- 5. How To Reset Root Password on RHEL 7 4 | P a g e Set – Root Password Now, After running the “chroot” command; in the shell prompt run the command “passwd” along with login username “root” as below to set new password for the root user. After command execution, Enter the new password and re-enter the new password again. passwd root Relabel Filesystem – SELinux At boot time, init.rc checks for the existence of /.autorelabel. If this file exists, SELinux performs a complete file system relabel (using the /sbin/fixfiles -f -F relabel command), and then deletes /.autorelabel. To perform the check run the command and reboot the server; after rebooting you can login into the server with newly set password. touch /.autorelabel reboot