Linux RunLevel & Single-user mode & Rescue mode

Run level

init 6 = = REBOOT = = Shutdwon-r now restart

init 0 = = Shutdown-h now off

Single-User mode

Press any key---> Press E to edit the 2nd item in three seconds after startup and press E---press 1--> at the end and press B to start-up in a few seconds into single-user mode--Change the password and restart with password

Rescue mode

Disc Boot Mirror--Select the third item rescue installed system--> whether to select Network--and whether to mount the original system to the repair system, select continue--> use chroot/mnt/ Sysimage switch to the original system and select Shell--> to enter the original system cd/mnt/sysimage--> Edit VI etc/passwd If you want to change the passwd configuration file

Change the root password in rescue mode

1.chroot/mnt/sysimage (Prompt changes the original bash-4.1 becomes sh-4.1)

2.PASSWD Change Password

3.exit Exit and reboot

Linux RunLevel & Single-user mode & Rescue mode