A crontab line begins with the fields `*/10 8-17 * * 1-5`. When does the job run?
LPIC-1 Exam 102-500, objective 107. Administrative tasks 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
Not correct Ten minutes past every hour, between 08:00 and 17:00, Monday through Friday
Wrong. Ten minutes past the hour would be written as a plain 10 in the minute field. The */ prefix makes it a repeating step, not a single value.
Not correct Every 10 minutes, for 10 hours, on the first five days of each month
Wrong. The fourth field is the month and the fifth is the day of week; day of month is the third field, which here is *. 1-5 therefore selects weekdays, not the 1st to 5th of the month.
Not correct At 10 minutes past 08:00 and 17:00 only, on the first five days of the week
Wrong on both counts: 8-17 is a range covering every hour in between, not two separate hours, and */10 is a step rather than a single minute.
Correct Every 10 minutes, during the hours 08:00 to 17:59, Monday through Friday
Correct. */10 in the minute field is a step: minutes 0, 10, 20, 30, 40 and 50. 8-17 is an inclusive hour range, so the last run of the day starts at 17:50. 1-5 in the day-of-week field is Monday to Friday.
Why
Within a field, a comma lists values (0,15,30), a hyphen gives an inclusive range (8-17), and a slash gives a step over a range (*/10 is shorthand for 0-59/10 in the minute field). Steps may be combined with ranges, as in 8-17/2 for every second hour of the working day.
Where this comes from
- Cited
- LPI exam objective 107.2
- What it says
- Understand ranges, lists and step values in crontab fields.
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 107 and space the ones you get wrong.
More questions on this objective
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