'numsub_filter' => '(objectClass=organizationalUnit)', // with VLV, we also use numSubOrdinates to query the total number of records. Set this filter to get all numSubOrdinates attributes for counting
'sizelimit' => '0', // Enables you to limit the count of entries fetched. Setting this to 0 means no limit.
'timelimit' => '0', // Sets the number of seconds how long is spend on the search. Setting this to 0 means no limit.
'referrals' => true|false, // Sets the LDAP_OPT_REFERRALS option. Mostly used in multi-domain Active Directory setups
// definition for contact groups (uncomment if no groups are supported)
// for the groups base_dn, the user replacements %fu, %u, $d and %dc work as for base_dn (see above)