[rahul@surrey ~]$ dovecot --version
2.2.10
[rahul@surrey ~]$ dovecot -n
# 2.2.10: /etc/dovecot/dovecot.conf
# OS: Linux 3.10.0-514.10.2.el7.x86_64 x86_64 CentOS Linux release 7.3.1611 (Core)  xfs
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_location = maildir:/home/vmail/%d/%n/Maildir
mail_plugins = " virtual"
namespace {
  inbox = yes
  location =
  prefix = INBOX.
  separator = .
  type = private
}
namespace {
  location = virtual:~/Maildir/All Mail
  prefix = All Mail.
  separator = .
  type = private
}
passdb {
  args = /etc/dovecot/dovecot-sql.conf.ext
  driver = sql
}
protocols = imap pop3
service auth-worker {
  user = root
}
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0666
    user = postfix
  }
  unix_listener auth-master {
    mode = 0600
    user = vmail
  }
  user = root
}
ssl_cert = </etc/pki/dovecot/certs/dovecot.pem
ssl_key = </etc/pki/dovecot/private/dovecot.pem
userdb {
  args = uid=5000 gid=5000 home=/home/vmail/%d/%n allow_all_users=yes
  driver = static
}
protocol lda {
  auth_socket_path = /var/run/dovecot/auth-master
  log_path = /home/vmail/dovecot-deliver.log
  postmaster_address = postmaster@surrey.local
}
protocol pop3 {
  pop3_uidl_format = %08Xu%08Xv
}