On the ypclient: In /etc/default/nis set NISCLIENT=true In /etc/yp.conf set the yp (master and slave) server IP addresses On the yp master+slave servers: In /etc/yp.conf set the yp (master and slave) server IP addresses In /etc/ypserv.securenets list all IP addresses of all yp clients so the ypserver accepts yp requests Andreas