# Module HowTo - Defining the RDN

Every LDAP DN starts with a RDN (relative DN). This is the value of a LDAP attribute. Users usually use "uid", groups use "cn".
You can provide a list of suitable RDN attributes for your module and give them a priority, too.
You will need to implement the function get_RDNAttributes() or use meta['RDN'].
Example:
The posixAccount module offers to create accounts with DNs uid=foo,dc=.... and cn=foo,dc=...
The uid attribute has a higher priority as it is the usual attribute for Unix accounts.
* Returns meta data that is interpreted by parent class
*
* @return array array with meta data
*/
function get_metaData() {
$return = array();
// RDN attributes
$return["RDN"] = array("uid" => "normal", "cn" => "low");
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