Dovecot and Postfix

[Jerry]

Does this configuration look sane? I seem to have a few duplicates and I am
not sure if that is a problem or not. It seems I have multiple "userdb"
sections and I am not sure where they are all originating from.

# 2.2.13: /usr/local/etc/dovecot/dovecot.conf
# OS: FreeBSD 10.0-RELEASE-p3 amd64  ufs
auth_debug_passwords = yes
auth_mechanisms = plain login
auth_verbose = yes
auth_verbose_passwords = plain
log_path = /var/log/dovecot
mail_location = maildir:/var/mail/vmail/seibercom/gerard
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave duplicate
namespace inbox {
  inbox = yes
  location = 
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix = 
}
passdb {
  args = username_format=%u /usr/local/etc/dovecot/user/passwd
  driver = passwd-file
}
passdb {
  driver = pam
}
passdb {
  args = scheme=CRYPT username_format=%u /usr/local/etc/dovecot/user/passwd
  driver = passwd-file
}
plugin {
  sieve_global_path = /usr/local/etc/dovecot/sieve/default.sieve
}
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
  unix_listener auth-userdb {
    group = vmail
    user = vmail
  }
}
ssl_cert = </etc/ssl/certs/dovecot.pem
ssl_key = </etc/ssl/private/dovecot.pem
userdb {
  args = username_format=%u /usr/local/etc/dovecot/user/passwd
  default_fields = uid=vmail gid=vmail
  driver = passwd-file
}
userdb {
  driver = passwd
}
userdb {
  args = username_format=%u /usr/local/etc/dovecot/user/passwd
  driver = passwd-file
}
protocol lda {
  mail_plugins = " sieve"
}