A SysV-init server currently boots into the graphical runlevel 5 and you must make it come up in the multi-user text runlevel 3 instead. Which line in /etc/inittab decides that?
LPIC-1 Exam 102-500, objective 110. Security medium
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How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.
The options
Correct id:3:initdefault:
Correct. The initdefault action tells init which runlevel to enter when booting without an explicit runlevel argument. The runlevel is taken from the second field and the process field is deliberately empty.
Not correct l3:3:wait:/etc/rc.d/rc 3
Wrong for choosing the default. This line says what to do on entering runlevel 3: run the rc script, which starts and stops the services linked under /etc/rc3.d, and wait for it to finish. It never selects the runlevel.
Not correct si::sysinit:/etc/rc.d/rc.sysinit
Wrong. The sysinit action runs once during boot before any runlevel is entered, which is why its runlevel field is empty. It performs early setup such as mounting filesystems.
Not correct 3:2345:respawn:/sbin/mingetty tty3
Wrong. This is a getty line: it starts a login prompt on tty3 in runlevels 2 to 5, and respawn restarts it whenever it exits. The leading 3 is just an entry identifier, not a runlevel.
Why
Every /etc/inittab line is id:runlevels:action:process, and the action keyword is what distinguishes these entries, not the digits. initdefault selects the boot runlevel and ignores its process field; wait, once and respawn describe how init treats the process it starts; sysinit runs before any runlevel. To move a machine without rebooting, telinit 3 switches immediately.
Where this comes from
- Cited
- manual page inittab(5)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 110 and space the ones you get wrong.
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