Adding the dovecot.conf configuration from old and new servers:

=========================================
My old server dovecot.conf (production1):
=========================================

disable_plaintext_auth = no

listen = *
log_path = /var/log/dovecot.log
mail_location = maildir:/z1dev/mail/virtual/%d/%n/Maildir/
passdb {
        args = /etc/dovecot/passwd
        driver = passwd-file
        master = yes
        pass = yes
        }
pop3_uidl_format = %g
protocols = pop3 imap
ssl = yes
ssl_cert = </etc/pki/dovecot/certs/dovecot.pem
ssl_key = </etc/pki/dovecot/private/dovecot.pem

userdb {
        args = uid=vmail gid=vmail home=/z1dev/mail/virtual/%d/%n
        driver = static
        }
mail_debug = no
verbose_ssl = no

=========================================
My New server dovecot.conf(production2):
=========================================

disable_plaintext_auth = no

listen = *
log_path = /var/log/dovecot.log

mail_location = maildir:/z1devenv/mail/virtual/%d/%n/Maildir/

passdb {
        args = /etc/dovecot/passwd
        driver = passwd-file
        }

pop3_uidl_format = %g
protocols = pop3 imap

ssl = yes
ssl_cert = </etc/pki/dovecot/certs/dovecot.pem
ssl_key = </etc/pki/dovecot/private/dovecot.pem

userdb {
        args = uid=vmail gid=vmail home=/z1devenv/mail/virtual/%d/%n
        driver = static
        }

mail_debug = yes
verbose_ssl = no


# Enable the replication plugin globally
mail_plugins = $mail_plugins notify replication

service replicator {
  process_min_avail = 1
}

dsync_remote_cmd = ssh -l%{login} %{host} doveadm dsync-server -u%u
plugin {
  mail_replica = remote:vmail@production3.baplc.com
}

service aggregator {
  fifo_listener replication-notify-fifo {
    user = vmail
  }
  unix_listener replication-notify {
    user = vmail
  }
}

service replicator {
  unix_listener replicator-doveadm {
    mode = 0600
    user = vmail
  }
}

replication_max_conns = 10

imapc_host = production1.baplc.com
imapc_password = vmail
imapc_master_user = vmail
imapc_user = %u

===================================

On Tue, Jul 28, 2020 at 8:44 PM Antonio Leding <tech@leding.net> wrote:

Not sure if this is the issue but the error says no password database is cfg’d…is that truly the case?  

Maybe post a redacted config for the community to review…

On Jul 28, 2020, at 7:20 AM, Kishore Potnuru <kishore.reachme@gmail.com> wrote:

Hi Aki & Dovecot team,

Just continuing with the previous discussion "Migration from one server to 2 new servers".

Hi,

I have tried the same way as per your suggestion. But it's throwing an error.

-------------
[root@production2 log]# doveadm backup -a All -R -u kishore@test.ba.com imapc:
dsync(kishore@test.ba.com): Info: imapc(production1.baplc.com:143): Connected to xxx.xxx.xxx.xxx:143 (local yyy.yyy.yyy.yyy:45992)
dsync(kishore@test.ba.com): Warning: imapc(production1.baplc.com:143): connect(xxx.xxx.xxx.xxx, 143) timed out after 30 seconds - reconnecting (delay 0 ms)
dsync(kishore@test.ba.com): Info: imapc(production1.baplc.com:143): Connected to xxx.xxx.xxx.xxx:143 (local yyy.yyy.yyy.yyy:46014)
dsync(kishore@test.ba.com): Error: imapc(production1.baplc.com:143): connect(xxx.xxx.xxx.xxx, 143) timed out after 30 seconds - disconnecting
dsync(kishore@test.ba.com): Error: User initialization failed: imapc: Login to production1.baplc.com failed: Disconnected from server
[root@production2 log]#
--------------

I looked into the production1 (old server) logs. I see the below error.

===============
Jul 28 11:14:23 auth: Fatal: Master passdb can't have pass=yes if there are no passdbs
Jul 28 11:14:23 master: Error: service(auth): command startup failed, throttling
===============

after the above error, I have commented "pass=yes" in production1 (old server) server, then I see the below error.

================
Jul 28 11:17:10 auth: Fatal: No passdbs specified in configuration file. PLAIN mechanism needs one
Jul 28 11:17:10 master: Error: service(auth): command startup failed, throttling
===============

Please suggest me on fixing the issue.