Mail Transport Agent (Mta) Configuration - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

Chapter 24. Email
24.3.3.5. Fetchmail Command Options
Most Fetchmail options used on the command line when executing the fetchmail command mirror
the .fetchmailrc configuration options. In this way, Fetchmail may be used with or without a
configuration file. These options are not used on the command line by most users because it is easier
to leave them in the .fetchmailrc file.
There may be times when it is desirable to run the fetchmail command with other options for a
particular purpose. It is possible to issue command options to temporarily override a .fetchmailrc
setting that is causing an error, as any options specified at the command line override configuration file
options.
24.3.3.6. Informational or Debugging Options
Certain options used after the fetchmail command can supply important information.
• --configdump — Displays every possible option based on information from .fetchmailrc and
Fetchmail defaults. No email is retrieved for any users when using this option.
• -s — Executes Fetchmail in silent mode, preventing any messages, other than errors, from
appearing after the fetchmail command.
• -v — Executes Fetchmail in verbose mode, displaying every communication between Fetchmail
and remote email servers.
• -V — Displays detailed version information, lists its global options, and shows settings to be used
with each user, including the email protocol and authentication method. No email is retrieved for any
users when using this option.
24.3.3.7. Special Options
These options are occasionally useful for overriding defaults often found in the .fetchmailrc file.
• -a — Fetchmail downloads all messages from the remote email server, whether new or previously
viewed. By default, Fetchmail only downloads new messages.
• -k — Fetchmail leaves the messages on the remote email server after downloading them. This
option overrides the default behavior of deleting messages after downloading them.
• -l <max-number-bytes> — Fetchmail does not download any messages over a particular size
and leaves them on the remote email server.
• --quit — Quits the Fetchmail daemon process.
More commands and .fetchmailrc options can be found in the fetchmail man page.

24.4. Mail Transport Agent (MTA) Configuration

A Mail Transport Agent (MTA) is essential for sending email. A Mail User Agent (MUA) such as
Evolution, Thunderbird, and Mutt, is used to read and compose email. When a user sends an email
from an MUA, the message is handed off to the MTA, which sends the message through a series of
MTAs until it reaches its destination.
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