unix:lmtp vs /usr/cyrus/bin/deliver ?

[Thomas Hannan]

Hi all,

I'm working on a Postfix+Cyrus IMAPd system, and am looking at whether to
have Postfix deliver mail to Cyrus via a unix lmtp socket
(/var/imap/socket/lmtp)
in /etc/postfix/main.cf:
mailbox_transport (or local_transport) = lmtp:unix:/var/imap/socket/lmtp
in /etc/postfix/master.cf:
  lmtp     unix   -    -    n   -    -   lmtp
and in /etc/cyrus.conf under SERVICES:
lmtpunix cmd="lmtpd" listen="/var/imap/socket/lmtp" prefork=1

**OR** use /usr/cyrus/bin/deliver as follows:

in /etc/postfix/master.cf
cyrus     unix  -       n       n       -       -       pipe
  flags= user=cyrus argv=/usr/cyrus/bin/deliver -r ${sender} -m
${extension} ${user}
in /etc/postfix/main.cf:
mailbox_transport = cyrus

Are there any performance/security issues using one method versus the
other? Would one offer me greater flexibility in doing spam filtering (via
regex and/or blacklists), antivirus checking, etc?

We handle mail for 3 domains, and don't have anything too fancy set up for
user authentication on the IMAP side...

Thanks much!
Thomas Hannan