Which of the following are mail transfer agents, that is, programs whose job is to accept and relay mail between systems using SMTP? (Choose three.)
LPIC-1 Exam 102-500, objective 108. Essential system services 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
Choose 3.
Not correct procmail
Not an MTA. procmail is a mail delivery agent: it takes a message the MTA has already accepted and files it into folders according to local rules.
Correct exim
An MTA. Exim is the default MTA on Debian and is configured through /etc/exim4 on that distribution.
Correct postfix
An MTA. Postfix was written as a modular, security-focused replacement for Sendmail and is the default on many current distributions.
Not correct fetchmail
Not an MTA. fetchmail is a retrieval agent: it collects mail from a remote POP3 or IMAP mailbox and hands it to the local MTA for delivery.
Correct qmail
An MTA. qmail is an older modular MTA, still named in the LPI objectives as one of the implementations to be aware of.
Why
The objective asks only for awareness of the common MTAs — sendmail, postfix, exim and qmail — plus the ability to forward mail and manage aliases. Full MTA configuration is outside LPIC-1. It helps to keep the roles distinct: the MTA moves mail between hosts over SMTP, the MDA (procmail, maildrop, dovecot's LDA) files an accepted message into a mailbox, the MUA is the client the human uses, and fetchmail pulls mail down from a remote server.
Where this comes from
- Cited
- LPI exam objective 108.3
- What it says
- Awareness of commonly available MTA programs.
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
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