A systemd host was installed with the wrong region and reports timestamps in UTC. Every user on it should see local time for Europe/Lisbon from now on. Which command makes that the system-wide setting?

LPIC-1 Exam 102-500, objective 108. Essential system services medium

Machine-checked — no person has signed for it. This question was read against the source cited below by an automated pass, which found no contradiction. That is a weaker claim than it sounds: the same kind of process wrote the question, so it can confirm its own mistake.

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 timedatectl set-timezone Europe/Lisbon

Correct. set-timezone takes a zone name from the tz database and repoints /etc/localtime at the matching file under /usr/share/zoneinfo, which is what the C library reads when formatting local time.

Not correct timedatectl set-time Europe/Lisbon

Wrong. set-time expects a date and time string such as "2026-08-18 09:30:00". Handing it a zone name is a syntax error, and even if accepted it would move the clock rather than change the zone.

Not correct timedatectl set-local-rtc 1

Wrong. That tells the system to keep the hardware clock in local time instead of UTC, a compatibility setting for dual-boot machines. It does not change which zone the system considers local.

Not correct export TZ=Europe/Lisbon

Wrong for a system-wide change. The TZ environment variable overrides the zone for the current shell and the processes it starts, and it disappears with that shell. It is useful for one-off conversions, not for configuring the host.

Why

The system zone is expressed by /etc/localtime, normally a symlink into /usr/share/zoneinfo; Debian-derived systems additionally keep the zone name as plain text in /etc/timezone. `timedatectl list-timezones` prints the valid names, which are Area/Location pairs and are case-sensitive. A per-process override with TZ always wins over /etc/localtime for that process.

Where this comes from

Cited
manual page timedatectl(1)

Practise this

Reading one question is not practice. The trainer will draw a short set from objective 108 and space the ones you get wrong.

Practise LPIC-1 Exam 102-500

More questions on this objective

All questions on Essential system services

Practise LPIC-1 Exam 102-500