Dec 29 16:06:40 mail-ha01 postfix/master[10619]: daemon started -- version 2.4.6, configuration /etc/postfix
Dec 29 16:06:40 mail-ha01 postfix/qmgr[10625]: B5844754AD: from=<test@webseite.name>, size=2561, nrcpt=1 (queue active)
Dec 29 16:06:40 mail-ha01 postfix/pipe[10629]: B5844754AD: to=<respond@dorijan.de>, relay=dovecot, delay=476, delays=475/0.06/0/0.11, dsn=4.3.0, status=deferred (temporary failure. Command output: Warning: Growing pool 'Environment' with: 4096 )
Dec 29 16:06:56 mail-ha01 postfix/postfix-script[10665]: stopping the Postfix mail system
Dec 29 16:06:56 mail-ha01 postfix/master[10619]: terminating on signal 15

master.cf
mail-ha01 postfix # cat master.cf |grep dovecot
dovecot   unix  -       n       n       -       -       pipe
  flags=DRhu user=vmail:mail argv=/usr/libexec/dovecot/deliver -d ${recipient}