diff -up dovecot-2.3.0.1/dovecot.service.in.waitonline dovecot-2.3.0.1/dovecot.service.in
--- dovecot-2.3.0.1/dovecot.service.in.waitonline	2018-03-01 10:35:39.888371078 +0100
+++ dovecot-2.3.0.1/dovecot.service.in	2018-03-01 10:36:29.738784661 +0100
@@ -12,6 +12,7 @@ After=local-fs.target network-online.tar
 
 [Service]
 Type=simple
+ExecStartPre=/usr/libexec/dovecot/prestartscript
 ExecStart=@sbindir@/dovecot -F
 PIDFile=@rundir@/master.pid
 ExecReload=@bindir@/doveadm reload