Run levels in Linux
A Linux system can be in specific run level. Linux system usually can have 7 run level (0-6).
0 run level is used to shut down the system.
6 run level is used to reboot the system.
Run levels 1 to 5 are used to start the system in single user or multi user mode and with or without networking.
We can use below command to check run level of the system.
$ who -r
To know which processes will start in any of the run level, you can use below command.
You can use below command to shut down the system.
$ init 0
You can use below command to restart the system.
$ init 6