4 なぜデフォルト MTA を dma にしたのか？

1. コミットログには

   commit a67b925ff3e58b072a60b633e442ee1d33e47f7f
   Author: Baptiste Daroussin <bapt@FreeBSD.org>
   Date:   Thu Oct 13 11:37:21 2022 +0200
   
       mail: make The Dragonfly Mail Agent (dma) the default mta.
       
       dma accepts mail from a local Mail User Agent (MUA) and delivers it
       locally or to a smarthost for delivery. dma does not accept inbound
       mail (i.e., it does not listen on port 25) and is not intended to
       provide the same functionality as a full MTA like postfix or sendmail.
       It is intended for use cases such as delivering cron(8) mail. which
       is the default configuration and usage of sendmail in the default
       setup of the base system.
       
       In order to switch the default from sendmail to dma, we teach
       mailwrapper to fallback on dma directly if the mailer.conf file cannot
       be opened.
       We install by default a mailer.conf file which points at dma
       We install a mailer.conf file for sendmail in the examples.
       
       Relnotes:       yes
       Differential Revision:  https://reviews.freebsd.org/D37035

   要するに

   1. そもそもメールはデフォルトではcronなどのローカル配送にしか使わない
   2. その用途に図体の大きいpostfixやsendmailは不用
   3. sendmailを使いたければexamplesにmailer.confを置いとくのでそれをコピーすれば良いだろう

   とうことらしい

2. いや，/etc/default/rc.confで

   sendmail_enable="NONE"	# Run the sendmail inbound daemon (YES/NO/NONE).
   			# If NONE, don't start any sendmail processes.
   sendmail_pidfile="/var/run/sendmail.pid"	# sendmail pid file
   sendmail_procname="/usr/sbin/sendmail"		# sendmail process name
   sendmail_flags="-L sm-mta -bd -q30m" # Flags to sendmail (as a server)
   sendmail_cert_create="YES"	# Create a server certificate if none (YES/NO)
   #sendmail_cert_cn="CN"   	# CN of the generate certificate
   sendmail_submit_enable="YES"	# Start a localhost-only MTA for mail submission
   sendmail_submit_flags="-L sm-mta -bd -q30m -ODaemonPortOptions=Addr=localhost"
   				# Flags for localhost-only MTA
   sendmail_outbound_enable="YES"	# Dequeue stuck mail (YES/NO).
   sendmail_outbound_flags="-L sm-queue -q30m" # Flags to sendmail (outbound only)
   sendmail_msp_queue_enable="YES"	# Dequeue stuck clientmqueue mail (YES/NO).
   sendmail_msp_queue_flags="-L sm-msp-queue -Ac -q30m"
   				# Flags for sendmail_msp_queue daemon.
   sendmail_rebuild_aliases="NO"	# Run newaliases if necessary (YES/NO).

   とか入っている時点でマズイでしょ．

3. ということでfreebsd-current MLに投げるも
   1. /etc/rc.d/sendmail起動時に告知した方が良いのではないか？[1]と投げたところ

   2. その返答はいつもの「src/UPDATING 20221205を見ろ」[2]だった;-(

      20221205:
      	dma(8) has replaced sendmail(8) as the default mta.  For people willing
      	to reenable sendmail(8):
      
      	$ cp /usr/share/examples/sendmail/mailer.conf /etc/mail/mailer.conf
      
      	and add sendmail_enable="YES" to rc.conf.