The 'last_name' attribute is mandatory for contact objects in CA SDM.
If the last_name field is empty in Active Directory (AD), the contacts will not be imported/synced into CA SDM and the following error will appear in the STDLOG"
ldap_sync 10072 ERROR ldap_sync.c 348 pdm_ldap_import: Error updating Contact cnt:3321FF1B99D1C542B912DB4447F2776F (AHD03075:Required attribute Last Name is missing from object Contact)
1. Make sure that the last_name field in AD is NOT empty for contacts to be imported/synced into CA SDM
2. Use the following command to force the ldap_sync to access AD contacts with a defined last_name
pdm_ldap_sync -l "last_name NOT NULL"