Issue

• sendmail サービスが起動しません。
• sendmail サービスがソケットを作成しません。
• SMTP ソケットの作成時に問題が発生していることが sendmail サービスのステータスで確認できます。

 mail]# systemctl status sendmail
● sendmail.service - Sendmail Mail Transport Agent
   Loaded: loaded (/usr/lib/systemd/system/sendmail.service; enabled; vendor preset: disabled)
   Active: active (running) since Wed 2015-12-30 17:34:59 EST; 4s ago
  ExecStart=/usr/sbin/sendmail -bd $SENDMAIL_OPTS $SENDMAIL_OPTARG (code=exited, statu    s=0/SUCCESS)
  ExecStartPre=/etc/mail/make aliases (code=exited, status=0/SUCCESS)
  ExecStartPre=/etc/mail/make (code=exited, status=0/SUCCESS)
 Main PID:47008 (sendmail)
   CGroup:/system.slice/sendmail.service
           └─47008 /usr/sbin/sendmail -bd -q1h

systemd[1]:Starting Sendmail Mail Transport Agent...
sendmail[47008]: starting daemon (8.14.7):SMTP+queuei...00
systemd[1]:PID file /run/sendmail.pid not readable (y...t.
sendmail[47008]:NOQUEUE:SYSERR(root): opendaemonsock...se
sendmail[47008]: daemon MTA: problem creating SMTP socket
systemd[1]:Started Sendmail Mail Transport Agent.
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