dovecot/templates/default/conf.d/auth-passwdfile.conf.ext.erb

# Authentication for passwd-file users. Included from auth.conf.
#
# passwd-like file with specified location.
# <doc/wiki/AuthDatabase.PasswdFile.txt>

passdb {
  driver = passwd-file
  args = scheme=CRYPT username_format=%u /etc/dovecot/users
}

userdb {
  driver = passwd-file
  args = username_format=%u /etc/dovecot/users
}