Exercise Summary (ii)--Ban ctrl+alt+delete, prohibit ordinary users to log on, prohibit ping

Exercise Source:http://www.aminglinux.com/bbs/thread-7679-1-1.html

Mistakes or vague questions to summarize:

3. How can I prevent others from forcing the system to restart by pressing Ctrl+alt+del before the server ?

Modify the following file:

[[Email protected]~]# vim/etc/init/control-alt-delete.conf

Comment out the last line.

5. What do you do when you do not want a regular user to log in when you are doing a heavy load operation on the server?

at first the idea was to lock all ordinary users through script usermod-l or passwd-l, or to change the login shell of all ordinary users from /bin/bash to c4>/sbin/nologin, both of these methods are also feasible, but not easy enough. The simplest and most violent way to unplug a network cable we certainly can't use it, but there's a more straightforward way to make a fuss about a network cable-- Create a nologin file in the/etc Directory :

[Email protected] ~]# Touch/etc/nologin

when you want to reply to a normal user's logon rights, you only need to delete the/etc/nologin file:

[Email protected] ~]# Rm-rf/etc/nologin

7. for security reasons, how do I make it possible for someone else to ping your online server?

This method in the Reiqing teacher's three video has been said, just because it is more difficult to remember so forget, review here, deepen the impression:

[Email protected] ~]# echo 1 >/proc/sys/net/ipv4/icmp_echo_ignore_all

This article is from the "barrel of fake dog excrement" blog, please be sure to keep this source http://xitongjiagoushi.blog.51cto.com/9975742/1627126

Exercise Summary (ii)--Ban ctrl+alt+delete, prohibit ordinary users to log on, prohibit ping