[Koha] management of consortium

hi all i want to know if i have libraries consortium and i need every library see her records only from opac or stuff is their any configuration available from administration to do that or the data will be searchable for all branches the second could we change the opac interface for every library in the consortium when the user of this library enter with his user name and password Mohamed El Zalabany Integrated library systems consultant LibroTech for library systems and information technology http://www.librotech.net mh_zalabany@hotmail.com Mobile: 0111291444