The LDAP passwords are stored encrypted so there’s no way to migrate without using bad methods like storing the passwords in clear text.
SSP provides different password reset methods:
- SMS
- Questions: You may use ssp some time before the migration to let users enter their answers to the questions so they could reset their password by answering a question after the migration.
- Mail: If the users got mail accounts not managed by Nethserver, they could reset their password by email
Phone numbers, answers or mail addresses have to be migrated from LDAP (ldapsearch) to samba (ldbmodify).
phpldapadmin or LAM support LDAP import/export but I never tested.