postfix ：
MUA: mutt mail (Linux)
Mail Relay: Mail relaying
the MTA: sendmail, qmail, postfix, Exim
postfix: Modular design
postconf
-a: server-side support SASL plug-type
-e: PARA of VALUE = br /> root @ mail .tom.com
-> e-mail address masquerading [email protected]
message field is required
to allow the use of a reference value parameter $ + other variables
MRA: cyrus-imap, Dovecot
Dovecot rely mysql client
pop3: 110 / tcp
IMAP4: 143 / tcp
in the clear work
dove supports four protocols: pop3, imap4, pops, imaps
profile: /etc/dovrcot.conf
have SASL authentication capabilities
mailbox formats:
mbox: a file storing all messages;
Maildir: a file storing a message, all messages stored in a directory;