1.不是每个用户都可以成为超级用户，因此 /bin/su的执行是受限于特定的组的，请问如何实现？请列出详细步骤！谢谢！
Not every user should be able to become superuser (root). Therefore the execution ofshould be restricted to a specified (new) group of users.
Explain the steps to realize such a restriction.？

2.Debian for example disables the remote use of the X-server by default. In other Linux
distributions the relevant tcp port is sometimes opened which might be a security risk. How can you
close this port and disable remote connections (necessary file configuration)?