Single User Mode

This method should also work on EL7 and EL8.

If you are unable to log-in to your system and have physical access, you can use single user mode to boot into it and do things like:

• Reset forgotten root password
• Fix configuration and other boot issues
• Repair filesystem if it is corrupted

• Reboot your machine and at grub menu choose a kernel and hit “e” to enter edit mode

• Append “rd.break” (w/o quotes) at the end of line that says “… /vmlinuz-3.x.. root=…”

• Hit Ctrl-x to boot into this kernel as single user

• Now remount the /sysroot in ‘rw’ mode as follows:

mount -o remount,rw /sysroot
chroot /sysroot

Fix the issue or use “passwd” to change password.

Finish the process (and reboot) by executing

touch /.autorelabel
reboot -f