The tool reads NIS directly from any client that can run Java 1.5 or better. Using JNDI to read NIS data and converts the data to an LDIF file for importing to LDAP.
An advantage of this method is that there is no need to export the NIS data as it is read live. We also have worked on a method to sync the NIS data to LDAP.
We have used this tool on several large conversions of NIS to LDAP and it is very fast and so far works well.