A nightly backup script must mail the contents of /var/log/backup.log to ops@example.com with the subject line Backup report, without any interactive prompting. Which command does that?
LPIC-1 Exam 102-500, objective 108. Essential system services easy
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 mail -s "Backup report" ops@example.com < /var/log/backup.log
Correct. -s supplies the subject non-interactively, the recipient is a plain argument, and redirecting a file onto standard input supplies the body so nothing is read from the terminal.
Not correct mail -c "Backup report" ops@example.com < /var/log/backup.log
Wrong option. -c takes a carbon-copy recipient list, so this would try to send a copy to a nonexistent address called Backup report and would still prompt for a subject.
Not correct mail -s ops@example.com "Backup report" < /var/log/backup.log
Wrong order. The argument after -s is consumed as the subject, so the message would be sent with the subject ops@example.com to a recipient called Backup report.
Not correct mail ops@example.com -f /var/log/backup.log -s "Backup report"
Wrong. -f tells mail to read an existing mailbox file rather than send anything, so this switches the program into reading mode instead of composing a message.
Why
mail is a mail user agent: it composes a message and hands it to the local MTA for delivery, it does not deliver anything itself. In non-interactive use the body comes from standard input and ends at end of file, which is why redirection works; typed interactively the body ends at a line containing only a full stop. Remember -s for subject, -c for carbon copy, -b for blind carbon copy and -f to open a mailbox for reading.
Where this comes from
- Cited
- manual page mailx(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.
More questions on this objective
- You corrected the running system's clock with `date -s`, but after the next power cycle the machine came back with the old wrong time. Which command copies the corrected system clock into the hardware (RTC) clock? machine-checked
- On a systemd-based distribution, which file determines the local time zone used by the C library when formatting times? machine-checked
- A host runs chrony as its NTP client. Which command shows the list of time sources chrony is currently talking to and how it rates each one? machine-checked
- In /etc/ntp.conf you find the line `server 0.pool.ntp.org iburst`. What does the `iburst` keyword do? machine-checked
- A minimal systemd host synchronises its clock with systemd-timesyncd. Which statement about that service is accurate? machine-checked
- On a systemd host, type the single command that turns on automatic network time synchronisation (do not include a path). machine-checked