dovecot - Feb 2017 - postfix/smtpd[725]: fatal: no SASL authentication mechanisms

I haven't doveadm logs in /var/log/. Are they default in another place or
maybe should I turn on something?
My config (default passdb block and auth_mechanisms, nothing more changed):
root at vps342401:/etc/dovecot# doveconf -n
# 2.2.9: /etc/dovecot/dovecot.conf
# OS: Linux 3.13.0-100-generic x86_64 Ubuntu 14.04.5 LTS
auth_mechanisms = plain login
listen = *,[::]
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_max_userip_connections = 100
mail_plugins = " quota"
mail_privileged_group = vmail
passdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
plugin {
  quota = dict:user::file:/var/vmail/%d/%n/.quotausage
  sieve = /var/vmail/%d/%n/.sieve
  sieve_max_redirects = 25
}
postmaster_address = postmaster at vps342401.ovh.net
protocols = imap pop3
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
  unix_listener auth-userdb {
    group = vmail
    mode = 0600
    user = vmail
  }
  user = root
}
service imap-login {
  client_limit = 1000
  process_limit = 512
}
service lmtp {
  unix_listener /var/spool/postfix/private/dovecot-lmtp {
    group = postfix
    mode = 0600
    user = postfix
  }
}
ssl = required
ssl_cert = </etc/postfix/smtpd.cert
ssl_cipher_list = ECDHE-RSA-AES128-GCM-SHA256:EC
DHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDH
E-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-
AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-
ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-
SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-
RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-
SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-
AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-
GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:
AES128-SHA:AES256-SHA:AES:CAMELLIA:DES-CBC3-SHA:!aNULL:!
eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH-DSS-DES-CBC3-
SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA

ssl_dh_parameters_length = 2048
ssl_key = </etc/postfix/smtpd.key
ssl_prefer_server_ciphers = yes
ssl_protocols = !SSLv2 !SSLv3 !TLSv1 !TLSv1.1
userdb {
  driver = prefetch
}
userdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
protocol imap {
  mail_plugins = quota imap_quota
}
protocol pop3 {
  mail_plugins = quota
  pop3_uidl_format = %08Xu%08Xv
}
protocol lda {
  mail_plugins = sieve quota
  postmaster_address = webmaster at localhost
}
protocol lmtp {
  mail_plugins = quota sieve
  postmaster_address = webmaster at localhost
}

And my logs:
Error from mail.err:
Feb  1 09:50:01 vps342401 postfix/smtpd[699]: fatal: no SASL authentication
mechanisms
Feb  1 09:51:02 vps342401 postfix/smtpd[724]: fatal: no SASL authentication
mechanisms
Feb  1 09:51:02 vps342401 postfix/smtpd[725]: fatal: no SASL authentication
mechanisms
Feb  1 09:52:21 vps342401 postfix/smtps/smtpd[773]: fatal: no SASL
authentication mechanisms

Error from syslog:
Feb  1 09:52:21 vps342401 postfix/smtps/smtpd[773]: connect from
host9323131.internet.3s.com[12.34.45.56]
Feb  1 09:52:21 vps342401 postfix/smtps/smtpd[773]: fatal: no SASL
authentication mechanisms
Feb  1 09:52:22 vps342401 postfix/master[29133]: warning: process
/usr/lib/postfix/smtpd pid 773 exit status 1
Feb  1 09:52:22 vps342401 postfix/master[29133]: warning:
/usr/lib/postfix/smtpd: bad command startup -- throttling
Feb  1 09:53:01 vps342401 CRON[777]: (root) CMD
(/usr/local/ispconfig/server/server.sh 2>&1 | while read line; do echo
`/bin/date` "$line" >> /var/log/ispconfig/cron.log; do  ne)
Feb  1 09:53:01 vps342401 CRON[778]: (root) CMD
(/usr/local/ispconfig/server/cron.sh 2>&1 | while read line; do echo
`/bin/date` "$line" >> /var/log/ispconfig/cron.log; done  )


Is there any strange thing in these config lines?

-- 

*Pozdrawiam / Best Regards*
*Piotr Bracha*




*tel. 534 555 877*

*serwis at poliman.pl <serwis at poliman.pl>*