Linux single-user password cracking

Linux single-user password cracking

Ubunt
1. When the system is started to grub, use the up/down key to move to the recovery mode of the second line, and press e (note not to press Enter)
That is, Ubutn, kernel 2.6.12-9-386 (recovery mode)
2. Change ro single to rw single init =/bin/bash and press ctrl + x

RHEL 6/centos 6
1. grub
After entering the startup screen, press "e", move the cursor to the line of kernel..., then press "e", add a space single at the end of the line of kernel, and press Enter.
Press "B" to start the system, that is, enter the single-user mode,
At this time, you can use the passwd command to change the password.
Passwd root
Restart reboot after modification.
2. lilo
Enter the lilo command line mode, and input linux single to enter the single user mode.



REHL7/Centos 7 (grub2)
If you have lost or forgot root password of RHEL7, you can follow this step to change to a new password, this is different with the RHEL6 single-usermode,

1. press e button in GRUB 2 boot screen.
2, at the end of Linux line add init =/bin/sh and remove 'rhg' and 'quiet'
3, Ctrl + x to boot the system with the parameter
4, remount the file system as writable, run the mount-o remount, rw/command
5. passwd to change password.
6. make sure SELinux context of the files that were modified is restored, touch/. autorelabel
7. last step, resume the initialization and finish the system boot. exec/sbin/init

1. Add init =/bin/sh to remove 'rhg' and 'quiet'
2. Ctrl + x
3. mount-o remount, rw/
4. passwd
5. touch/. autorelabel {When selinux is enabled}
6. exec/sbin/init
7. Enter a single user to display garbled characters using: LANG = zh-cn.utf8