1.Reboot the system.
2.Interrupt the boot loader count down by pressing anykey.
3.Move the cursor to the entry that needs to be booted.
4.Press “e” to edit the select edentry.
5.Move the cursor to the kernel command line(the line that start swith linux16.
6.Append rd.break
7.Press Ctrl+x to start.
8.Remount /sysroot as read-write.
switch_root:/# mount -o remount,rw /sysroot
9.Switch into a chroot jail, where /sysroot is treated as the root of the filesystem tree
switch_root:/# chroot /sysroot
10.Set a new root password:
sh-4.2# passwd [root] (change the root password)
or
sh-4.2# passwd -d root (delete the root password)
11.Make sure that all unlabeled files (including/etc/shadow at this point)get relabeled during boot.
sh-4.2# touch /.autorelabel
12. sh-4.2# exit
13. switch_root:/# exit
$ su -c passwd普通用户给root用户修改密码
破解root密码:
1、重启虚拟机
2、在linux16末尾加上 rd.break,ctrl+x执行
3、mount -o remount,rw /sysroot
4、chroot /sysroot
5、passwd root
6、输入新密码:
7、确认密码
8、touch /.autorelabel
9、exit
10、exit