Message Transfer Agent (email)

Question 1

MTA

Answer 1

Program (service daemon) routes email to intended destination
MTA -> MDA -> MUA

Question 2

sendmail

Answer 2

One of oldest, default, notoriously difficult to config.

Question 3

postfix

Answer 3

Modern on many. Simpler to config. Great security

Question 4

exim

Answer 4

Used to be default MTA for Debian, good security, easier than sendmail to configure.

Question 5

Sendmail Emulation Layer

Answer 5

Sysadmins can use sendmail-styled cmds on other MTAs as if managing sendmail.

Question 6

/etc/aliases

Answer 6

Plaintext, can be modified to set up forwarding addresses for users on system.
Aliases set up as :

Question 7

newaliases

Answer 7

Regenerates /etc/aliases.db

Question 8

mail

Answer 8

Send mail.
-s: subject
 Enters text writing application following options and recipient. End with EOT (Ctrl+d)
# to view prompt.
&:
    d: delete
    q: quit

Question 9

mailq

Answer 9

View mail queue waiting to sent.

Shows ID, size, arrival time, and sender/recipient.

Question 10

~/.forward

Answer 10

Local configuration file. Can be set up within user’s home directory to forward email destined for itself to be sent to another user and/or external email address.
\ for local.