在缺省情况下,当你登陆到linux系统,它会告诉你该linux发行版的名称、版本、内核版本、服务器的名称。对于黑客来说这些信息足够它入侵你的系统了。你应该只给它显示一个“login:”提示符。 首先编辑"/etc/rc.d/rc.local" 文件,在下面显示的这些行前加一个“#”,把输出信息的命令注释掉。 # This will overwrite /etc/issue at every boot. So, make any changes you # want to make to /etc/issue here or you will lose them when you reboot. #echo "" > /etc/issue #echo "$R" >> /etc/issue #echo "Kernel $(uname -r) on $a $(uname -m)" >> /etc/issue # #cp -f /etc/issue /etc/issue.net #echo >> /etc/issue 其次删除"/etc"目录下的“isue.net”和"issue"文件: # rm -f /etc/issue # rm -f /etc/issue.net