Linux Administration
medium
Questão de Linux Administration #019e3987
Enunciado da Questão
Linux Administration
#systemd
#upstart
#sysvinit
#init-system
#boot-process
Médio
D.
paste -f 1,4 /etc/passwd
Which of the following are init systems used within Linux systems? (Choose THREE correct answers.)
A
startd
B
systemd
Correta
C
Upstart
Correta
D
SysInit
E
SysV init
Correta
Explicação Oficial / Explicações da Comunidade
Summary
Linux systems have used several init systems over time. The correct init systems among the options are systemd, Upstart, and SysV init. These are the three that have been widely adopted in various distributions.
How It Works
An init system is the first process started by the kernel during boot (PID 1) and is responsible for bringing the system to a usable state. It manages services, daemons, and system states (runlevels or targets).
Correct Choices
- systemd: The modern init system used by most major distributions (Fedora, Ubuntu, Debian, RHEL, etc.). It uses unit files and targets, and provides parallel service startup, dependency management, and logging via journald.
- Upstart: Developed by Ubuntu as a replacement for SysV init, it uses event-driven job definitions. It was used in Ubuntu up to version 14.10 and in some other distributions before being replaced by systemd.
- SysV init: The traditional init system based on System V Unix. It uses runlevels (0-6) and scripts in
/etc/rc.d/or/etc/init.d/. It is still used in some distributions like Slackware and as a fallback.
Incorrect Choices
- startd: This is not a standard init system. It may be confused with
start-stop-daemonor similar tools, but it is not a recognized init system. - SysInit: This is not a real init system. It might be a misspelling or confusion with SysV init, but no such system exists.