dovecot - Nov 2017 - SMTP and IMAP authentication critically fails out of the blue

Hello Community and first things First:
dovecot --version2.2.9dovecot -n# 2.2.9: /etc/dovecot/dovecot.conf# OS: Linux
3.13.0-042stab125.5 x86_64 Ubuntu 14.04.5 LTSauth_mechanisms = plain logindict
{? sqlquota = mysql:/etc/dovecot/dovecot-dict-sql.conf}listen =
*,[::]log_timestamp = "%Y-%m-%d %H:%M:%S "login_log_format_elements =
user=<%u> method=%m rip=%r lip=%l mpid=%e %c %kmail_fsync =
alwaysmail_home = /var/vmail/%d/%nmail_location = maildir:~/mail_nfs_index =
yesmail_nfs_storage = yesmail_plugins = quota aclmanagesieve_notify_capability =
mailtomanagesieve_sieve_capability = fileinto reject envelope encoded-character
vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy
include variables body enotify environment mailbox date ihavemmap_disable =
yesnamespace {? list = yes? location = maildir:%%h/:INDEXPVT=~/Shared/%%u?
prefix = Shared/%%u/? separator = /? subscriptions = yes? type =
shared}namespace inbox {? inbox = yes? location =? mailbox Archiv {? ?
special_use = \Archive? }? mailbox Archive {? ? auto = subscribe? ? special_use
= \Archive? }? mailbox Archives {? ? special_use = \Archive? }? mailbox
"Deleted Messages" {? ? special_use = \Trash? }? mailbox Drafts {? ?
auto = subscribe? ? special_use = \Drafts? }? mailbox Entw?rfe {? ? special_use
= \Drafts? }? mailbox "Gel?schte Objekte" {? ? special_use = \Trash?
}? mailbox Gesendet {? ? special_use = \Sent? }? mailbox Junk {? ? auto =
subscribe? ? special_use = \Junk? }? mailbox Papierkorb {? ? special_use =
\Trash? }? mailbox Sent {? ? auto = subscribe? ? special_use = \Sent? }? mailbox
"Sent Messages" {? ? special_use = \Sent? }? mailbox Trash {? ? auto =
subscribe? ? special_use = \Trash? }? prefix =? separator = /}passdb {? args =
/etc/dovecot/dovecot-mysql.conf? driver = sql}plugin {? acl = vfile? acl_anyone
= allow? acl_shared_dict = file:/var/vmail/shared-mailboxes.db? quota =
dict:User quota::proxy::sqlquota? quota_rule2 = Trash:storage=+100%%? sieve =
/var/vmail/sieve/%u.sieve? sieve_after = /var/vmail/sieve/global.sieve?
sieve_max_script_size = 1M? sieve_quota_max_scripts = 0? sieve_quota_max_storage
= 0}protocols = imap sieve lmtp pop3service auth {? unix_listener
/var/spool/postfix/private/auth_dovecot {? ? group = postfix? ? mode = 0660? ?
user = postfix? }? unix_listener auth-master {? ? mode = 0600? ? user = vmail?
}? unix_listener auth-userdb {? ? mode = 0600? ? user = vmail? }? user =
root}service dict {? unix_listener dict {? ? group = vmail? ? mode = 0660? ?
user = vmail? }}service lmtp {? unix_listener
/var/spool/postfix/private/dovecot-lmtp {? ? group = postfix? ? mode = 0600? ?
user = postfix? }? user = vmail}service managesieve-login {? inet_listener sieve
{? ? port = 4190? }? process_min_avail = 2? service_count = 1? vsz_limit = 128
M}service managesieve {? process_limit = 256}ssl_cert =
</etc/ssl/mail/mail.crtssl_cipher_list =
EDH+CAMELLIA:EDH+aRSA:EECDH+aRSA+AESGCM:EECDH+aRSA+SHA384:EECDH+aRSA+SHA256:EECDH:+CAMELLIA256:+AES256:+CAMELLIA128:+AES128:+SSLv3:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!DSS:!RC4:!SEED:!ECDSA:CAMELLIA256-SHA:AES256-SHA:CAMELLIA128-SHA:AES128-SHAssl_dh_parameters_length
= 2048ssl_key = </etc/ssl/mail/mail.keyssl_protocols = !SSLv3 !SSLv2userdb {?
args = /etc/dovecot/dovecot-mysql.conf? driver = sql}protocol imap {?
mail_plugins = quota imap_quota imap_acl acl}protocol lmtp {? auth_socket_path =
/var/run/dovecot/auth-master? mail_plugins = quota sieve acl? postmaster_address
= postmaster at domain1.com}protocol sieve {? managesieve_logout_format =
bytes=%i/%o}remote 127.0.0.1 {? disable_plaintext_auth =
no}###########################################



Mail.errNov 13 23:59:06 webdev dovecot: auth: Error: PLAIN(account at
domain2.com, XXX.XXX.XXX.XXX,<y869CoDETEST4dHk>): Request 29154.1 timed
out after 150 secs, state=1###########################################


Mail.logNov 13 23:27:54 webdev dovecot: auth: Error: LOGIN(account at
domain1.com,IP.IP.IP.IP,<oN4ly+TestDZ6dHk>): Request 28118.1 timed out
after 150 secs, state=1Nov 13 23:27:57 webdev dovecot: auth: Error: PLAIN(
account at domain2.com,XXX.XXX.XXX.XXX,<FAxKe+JaatES7tHk>): Request
28120.1 timed out after 150 secs, state=1Nov 13 23:28:24 webdev dovecot:
imap-login: Disconnected: Inactivity during authentication (disconnected while
authenticating, waited 180 secs): user=<>, method=LOGIN, rip=ClientIP,
lip=ServerIP, TLS: Disconnected, TLSv1.2 ?with cipher DHE-RSA-AES128-GCM-SHA256
(128/128 bits)?[...]Nov 13 23:47:15 webdev dovecot: imap-login: Aborted login
(no auth attempts in 0 secs): user=<>, rip=84.119.151.17,
lip=62.75.185.32###########################################


I did not change anything on my client nor serverside setup and i suddenly could
not reach the Mailserver anymore. Obviously I can reach the Server using SSH or
HTTP.
I hope I?provided all infos you need to help me in this situation. And am
grateful for every hint to solve this

Note:?Older mailinglist threads did not help because a link which solved a
similar case is not available anymore.plus I tried to make the given pieces of
information structured using styles. Maybe it gets delivered,displayed and
enhances the ease of reading.

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On Tue, 14 Nov 2017, Felix Plapper wrote:
> Mail.errNov 13 23:59:06 webdev dovecot: auth: Error: PLAIN(account at
domain2.com, XXX.XXX.XXX.XXX,<y869CoDETEST4dHk>): Request 29154.1 timed
out after 150 secs, state=1
looks like the connection to your passdb (mysql) is not working.

- -- 
Steffen Kaiser
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