--enable-dns: This switch allows realms to be resolved using the DNS server. mv /bin/login /bin/login.shadow cp /usr/sbin/login.krb5 /bin/login mv /usr/bin/ksu /bin Preserves Shadow's login command, moves ksu and login to the /bin directory. mv /usr/lib/libkrb5.so.3* /lib mv /usr/lib/libkrb4.so.2* /lib mv /usr/lib/libdes425.so.3* /lib mv /usr/lib/libk5crypto.so.3* /lib mv /usr/lib/libcom_err.so.3* /lib ln -sf ../../lib/libkrb5.so /usr/lib ln -sf ../../lib/libkrb4.so /usr/lib ln -sf ../../lib/libdes425.so /usr/lib ln -sf ../../lib/libk5crypto.so /usr/lib ln -sf ../../lib/libcom_err.so /usr/lib The login and ksu programs are linked against these libraries, therefore we move these libraries to /lib to allow logins without mounting /usr.