Hack the password of a Linux virtual machine

Virtual machine hack Secret code step:

a virtual machine (server) login usually requires a local user, and the local user password if you do not know or have forgotten, there is a way to enter, in the Linux system can provide this access to the program, and the basic idea is to reset the administrator (root) login password , the following are the specific actions:
1, restart the virtual machine server, the GRUB boot menu when you press the E key to enter the editing state (in fact, you can restart the process of non-stop press the E entry to prevent the interface is not caught, the interface stays relatively short)

Restart the virtual machine on the restart above the point machine;

This interface is the grub interface, stay for a few seconds, in the presence of this interface when the E is not easy to catch, it is recommended to restart the interface before the appearance of press E, guaranteed to be able to enter the editing state;

This interface is the editing interface, you can press the upper and lower direction key to flip;

2, find linux16 line, add Rd.break console=tty0 at the end, press ctrl+x key into recovery mode

Locate the Linux16 line, and then press the end key to jump to the end of the position, enter " space ", enter the command rd.break console=tty0 , and then CTRL + X Enter recovery mode

3. Mount the root directory on the hard disk in a writable manner and reset the root password:

After entering recovery mode, enter the following command to re-mount the root system, switch to the root system, set the password specified in the exam, and mark the next start of the Redo SELinux label, and a series of operations.

switch_root:/# mount-o remount,rw/sysroot          // Re-mount the root system in a read-write manner
switch_root:/# chroot/sysroot/          &NBSP  //Switch to the root system
sh-4.2# passwd root      // Set the password specified for the exam     #sh -4.2# echo 123456 | passwd--stdin root    / /here or use this non-interactive way to set the password more concise   
sh-4.2# touch/.autorelabel       //mark next start Redo SELinux label
sh-4.2# exit
switch_root:/# reboot

4. Configure host name, IP address/mask/default gateway/DNS address
[Email protected] ~]# Hostnamectl set-hostname serverX.example.com
[Email protected] ~]# nmcli connection Modify "System eth0" Ipv4.method manual ipv4.addresses "172.25.x.11/24 172.25.x.25 4 "Ipv4.dns 172.25.254.254
[[email protected] ~]# nmcli connection Modify "System eth0" Connection.autoconnect Yes //Allow automatic connection when required
[[email protected] ~]# nmcli connection up "System eth0" //activating NIC configuration information

Hack the password of a Linux virtual machine