Hi

I am in the process/planning of moving from my existing dovecot imap/pop3 server to 2 new servers (for HA/Resilience). I will be implementing dovecot replication on new servers.  Please find my current and new servers versions.

My Current Production Server details:
========================
Linux OS        -  Red Hat Enterprise Linux Server release 6.5 (Santiago)
Dovecot version -  2.0.9
Postfix version -  2.6.6
========================

New Servers:
==========================
Linux OS        -  Red Hat Enterprise Linux Server release 7.7 (Maipo)
Dovecot version -  2.2.36 (1f10bfa63)
Postfix version -  2.10.1
==========================

What is the best way to stop/copy/migrate the current production data to the new servers? I am planning the following steps. Not sure if it is correct or not.

1. Stop the Postfix services on the old server and wait for few mins. So that no new emails will be coming to the old servers. Existing emails will be delivered to the receipients.

2. copy/migrate the data from old server to new servers. Please suggest what is the best way?

3. I see that dovecot version(2.0.9) in old production server, I do not know the which is the best option? see the options in the current version.

=================================
[root@prodcution ~]# doveadm
usage: doveadm [-Dv] [-f <formatter>] <command> [<args>]

  altmove      [-u <user>|-A] [-S <socket_path>] <search query>
  auth         [-a <auth socket path>] [-x <auth info>] <user> [<password>]
  config       [doveconf parameters]
  director     add|flush|map|remove|status
  dump         [-t <type>] <path>
  expunge      [-u <user>|-A] [-S <socket_path>] <search query>
  fetch        [-u <user>|-A] [-S <socket_path>] <fields> <search query>
  force-resync [-u <user>|-A] [-S <socket_path>] <mailbox>
  help         <cmd>
  import       [-u <user>|-A] [-S <socket_path>] <source mail location> <dest parent mailbox> <search query>
  kick         [-a <anvil socket path>] [-f] <user mask>[|]<ip/bits>
  log          find|reopen|test
  mailbox      create|delete|list|mutf7|rename|status|subscribe|unsubscribe
  penalty      [-a <anvil socket path>] [<ip/bits>]
  purge        [-u <user>|-A] [-S <socket_path>]
  pw           [-l] [-p plaintext] [-r rounds] [-s scheme] [-u user] [-V]
  reload
  search       [-u <user>|-A] [-S <socket_path>] <search query>
  sis          deduplicate|find
  stop
  user         [-a <userdb socket path>] [-x <auth info>] <user mask> [...]

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

Please suggest me.

Thanks,
Kishore Potnuru