You are auditing a systemd installation from a rescue system, with its filesystems mounted but nothing of it running, and must determine which target it boots into. Which item on disk records that choice?
LPIC-1 Exam 101-500, objective 101. System architecture medium
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Treat it as a good draft rather than as settled fact, and read the source below before you rely on it. It is not used in mock exams here — only questions a person has signed for are.
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 The symbolic link /etc/systemd/system/default.target
Correct. systemctl set-default creates or replaces this symlink, and `ls -l` on it names the target the machine will boot into.
Not correct /etc/inittab
Wrong. That is the SysVinit file whose initdefault line held the default runlevel. systemd does not read it; on many systemd distributions it is absent, or present only with a comment saying it is ignored.
Not correct /usr/lib/systemd/system/default.target
Wrong as the authoritative answer. A distribution may ship a default there, but anything with the same name under /etc/systemd/system takes precedence, so reading only the vendor path can report the wrong target.
Not correct /etc/systemd/system.conf
Wrong. system.conf configures the service manager itself, with settings such as DefaultTimeoutStopSec and LogLevel. It does not select a boot target.
Why
The default boot target is expressed as a symlink rather than a setting, which fits systemd's model of resolving unit names through the filesystem: booting means activating default.target, and what that name points at is the whole decision. Administrator units in /etc/systemd/system override same-named vendor units in /usr/lib/systemd/system, so a vendor default.target is only in effect while no local symlink exists. A kernel argument systemd.unit=... overrides both for one boot without changing anything on disk.
Where this comes from
- Cited
- manual page systemd.special(7)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 101 and space the ones you get wrong.
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