Linux Administration/System Architecture/Boot Configuration

This lesson covers boot configuration.

Objectives and Skills
Objectives and skills for the boot sequence portion of Linux+ certification include:
 * Change runlevels/boot targets and shutdown or reboot system.
 * Set the default runlevel or boot target
 * Change between runlevels/boot targets including single user mode
 * Shut down and reboot from the command line
 * Alert users before switching runlevels/ boot targets or other major system events
 * Properly terminate processes
 * The following is a partial list of the used files, terms and utilities:
 * /etc/inittab
 * shutdown
 * init
 * /etc/init.d
 * telinit
 * system
 * systemctl
 * /etc/systemd/
 * /usr/lib/system/
 * wall

Readings

 * 1)  Runlevel
 * 2)  Shutdown (computing)
 * 3)  init
 * 4) systemd
 * 5)  Upstart (software)
 * 6)  wall (Unix)

Multimedia

 * 1) YouTube: Working with Linux Runlevels
 * 2) YouTube: Properly Terminating Linux Processes
 * 3) YouTube: Init, Systemd, and Upstart

Activities

 * 1) Complete the tutorial IBM: Learn Linux, 101: Runlevels, boot targets, shutdown, and reboot
 * 2) Shutdown
 * 3) * Use  to shutdown the system.
 * 4) * Use  to shutdown the system.
 * 5) * Use  to shutdown the system.
 * 6) Reboot
 * 7) * Use  to reboot the system.
 * 8) * Use  to reboot the system.
 * 9) * Use  to reboot the system.
 * 10) * Use  to reboot the system in single-user mode.
 * 11) * Use  to reboot the system in single-user mode.
 * 12) Test the difference between   and.
 * 13) Set default runlevels.
 * 14) * Use  to configure multi-user mode. Reboot.
 * 15) * Use  to configure graphical user mode. Reboot.
 * 16) Review HowToForge: Linux wall Command Tutorial. Use   to alert users of an impending reboot.
 * 17) Use   to stop processes.
 * 18) * Review Benjamin Cane: Understanding the kill command, and how to terminate processes in Linux.
 * 19) * Run a user program, such as the calculator or an editor. Use  to find the program's process ID. Use   and the process ID to ask the program to terminate itself.
 * 20) * Run the program. Use  to find the program's process ID. Use   and the process ID to ask the program to terminate itself.
 * 21) * Run the program. Use  to find the program's process ID. Use   and the process ID to ask the program to terminate itself.
 * 22) * Run the program. Use  to find the program's process ID. Use   and the process ID to kill the process.
 * 23) * Run the program. Use  to find the program's process ID. Use   and the process ID to kill the process.
 * 24) Stop and restart services.
 * 25) Review CyberCiti.biz: Service command.
 * 26) * Use  to list service status.
 * 27) * Use  to stop the printing service.
 * 28) * Use  to start the printing service.
 * 29) * Use  to restart the printing service.

Lesson Summary

 * The  command will halt, poweroff, or reboot the system:
 * command stops CPU processing
 * stops CPU processing and powers off a system
 * reboots a system
 * The  command is used to terminate processes without having to log out or reboot the computer.
 * (SIGTERM, option 15) and signals the process to terminate itself
 * or  kills the process
 * The  command is used to start, stop, and restart services.
 * The  command turns off or reboots a computer.
 * shuts down a system immediately
 * reboots a system
 * The  command is used to examine and control the state of "systemd".
 * changes the runlevel
 * sets the default runlevel
 * runlevels include:
 * 0 -
 * 1 -
 * 3 -
 * 5 -
 * 6 -
 * The  command signals   to change runlevels. Runlevels include:
 * 0 - halt
 * 1 - single-user mode
 * 6 - reboot
 * The  command (write to all) displays the contents of a file or standard input to all logged-in users.
 * contains start/stop scripts for system services.
 * is the top-level configuration file for init.
 * contains local systemd configuration files.