how to rd.break and be a HACKER (developed on CentOS 7) method 1: reboot arrow keys at GRUB e to edit GRUB kernel boot parameters erase junk add useful stuff: rd.break rw Ctrl+X # to continue booting chroot /sysroot # to get yrself into an environment where yr tools look in the right dirs for themselves passwd root # the real hackering touch /.autorelabel # make SELinux not freak upon next boot Ctrl+D twice # to exit the rd.break environment and continue booting method 2: e to edit GRUB add useful stuff: systemd.debug-shell=1 Ctrl+X # to continue booting Ctrl+Alt+f9 # to switch to the debug-shell TTY. a root session will be there logged in passwd root systemctl stop debug-shell # undo the horrifically unsecure thing you just did to yr system Ctrl+Alt+f1 # and login method 3: e to edit GRUB add params: rw rd.break enforcing=0 chroot /sysroot passwd root Ctrl+D twice # NO LOGOUT tho, careful!! continue booting ONLY login restorecon -Rv /etc # or possibly just /etc/shadow? now safe to reboot if no reboot, do: setenforce=1 # to turn SELinux back on half-method 4: e to edit GRUB add params: init=/bin/bash # can use similarly to rd.break and get into system all hackerly and cool # but the environment is weird and rebooting is confusing # you CAN use passwd and /.autorelabel like normal # but is just weird. # maybe test more later notes: if you don't use "rw" on the kernel boot param line, you have to remount /sysroot with rw after rdbreaking ex.: mount -o remount,rw /sysroot in GRUB, kernel boot params that come later take precedence over those that come first thus you can add "rw rd.break" to the end of the long string of junk without having to worry about going back and erasing the part that says "ro" other kernel boot parameters: nomodeset # good for video card trouble # turn off Kernel Mode Setting (KMS) which is "a method for setting display resolution and depth in the kernel space rather than user space" -ArchLinux Wiki quiet splash # often used together # hide boot messages to avoid alarming people # show a pretty splash screen rhgb # Red Hat Graphical Boot # like splash but RHEL-customized for RHEL-family OSes to permanently edit kernel boot parameters: note that, when you change with "e to edit GRUB", changes only last thru that individual boot permanent edits go like: vi /etc/default/grub GRUB_CMDLINE_LINUX_DEFAULT="<edits go here!!!!>" then regen grub with: grub-mkconfig -o /boot/grub/grub.cfg (please note that this segment of instructions not yet tested by the author) references: