Linux reset root password and machine log in to each other

Single-User mode

• System restart command: Reboot init 6 shutdown-r now
• Shutdown command: Init 0 poweroff
• Operating level: 0-6

    [[email protected] ~]# ls-l/usr/lib/systemd/system/runlevel*targetlrwxrwxrwx. 1 root root 15 May 28 18:4 8/usr/lib/systemd/system/runlevel0.target-Poweroff.target # # #关机lrwxrwxrwx. 1 root root 13 May 18:48/usr/lib/systemd/system/runlevel1.target-Rescue.target # # #单用户lrwxrwxrwx. 1 root root 17 May 18:48/usr/lib/systemd/system/runlevel2.target-Multi-user.target # # #多用户lrw Xrwxrwx. 1 root root 17 May 18:48/usr/lib/systemd/system/runlevel3.target-Multi-user.target # # #多用户 LR Wxrwxrwx. 1 root root 17 May 18:48/usr/lib/systemd/system/runlevel4.target-Multi-user.target # # #多用户 LR Wxrwxrwx. 1 root root 16 May 18:48/usr/lib/systemd/system/runlevel5.target-Graphical.target # # #图像界面lrwxrwxrwx . 1 root root 13 May 18:48/usr/lib/systemd/system/runlevel6.target-Reboot.target # # #重启  
  

• Enter single-user mode to modify the root password: requires a grub password or is not encrypted
• Restart the system, press the UP and down keys
  
• Press E to enter grub to find the RO position modification
  
• Change ro to RW init=/sysroot/bin/sh
  
• Press CTRL + X to enter a command-line interface similar to safe mode
  Enter the following command to change the root password and restart directly.
  Rescue mode
• Enter rescue mode to change the root password:
  Set up virtual machine mirroring
  
  Click on the virtual machine power supply, select Enter BIOS at startup, move CD-ROM drive to the first, F10 save to exit.
  
  Go to the Installation screen and select the third item
  
  Select the second item
  
  Enter into the carriage return and type 1
  
  Enter a command line mode after carriage return
  
  Enter the following command to modify the root password, restart the system, and do not forget to modify the boot system from the hard disk.
  Cloning a virtual machine

  Use a virtual machine to clone a virtual machine without a full clone.
  Configure the IP address of the clone machine
  Modify hostname: This command is a direct change to the configuration file/etc/hostname
  

  Linux Machine Mutual Login configuration if aminglinux-02 needs to log on aminglinux-01:
• Operating on the aminglinux-02

    [[email protected] ~]# ssh-keygen        配置密钥Generating public/private rsa key pair.     Enter file in which to save the key (/root/.ssh/id_rsa):      指定目录Enter passphrase (empty for no passphrase):                  设置密码             Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa.       私钥保存目录Your public key has been saved in /root/.ssh/id_rsa.pub.      公钥保存目录The key fingerprint is:79:cd:12:34:d1:54:c0:58:de:38:52:7e:eb:d4:61:6d [email protected]The key‘s randomart image is:+--[ RSA 2048]----+|          +B=o.  ||         ..=oo  .||          o = ooE||         . = o.+.||        S o o o .||         . . o   ||              .  ||                 ||                 |+-----------------+[[email protected] ~]# ls /root/.ssh/authorized_keys  id_rsa  id_rsa.pub  known_hosts

• Copy the public key inside the id_rsa.pub into the/root/.ssh/authorized_keys inside the aminglinux-01.
  

• Connection aminglinux-01
  

• Firewall command

  [[email protected] ~]# getenforce           查看selinux状态Enforcing                                                     开启                                     [[email protected] ~]# setenforce 0        临时关闭[[email protected] ~]# getenforce                  Permissive                                                  关闭                     

Linux reset root password and machine log in to each other