man手册对/etc/issue文件的描述是：
The file /etc/issue is a text file which contains a message or system identification to be printed before the login prompt. It may contain various @char and \char sequences, if supported by getty.
如上所述，修改/etc/issue文件可以达到修改登录提示语的作用。修改并保存该文件之后，重启，重启完成之后，按组合键Ctrl+Alt+F1进入终端模式，你就可以看到修改之后的提示语了。
/etc/issue - escape code
The issue-file (/etc/issue or the file set with the -f option) may contain certain escape codes to display the system name, date and time etc. All escape codes consist of a backslash (\) immediately followed by one of the letters explained below.
\b : Insert the baudrate of the current line.
\d : Insert the current date.
\s : Insert the system name, the name of the operating system.
\l : Insert the name of the current tty line.
\m : Insert the architecture identifier of the machine, eg. i486
\n : Insert the nodename of the machine, also known as the hostname.
\o : Insert the domainname of the machine.
\r : Insert the release number of the OS, eg. 1.1.9.
\t : Insert the current time.
\u : Insert the number of current users logged in.
\U : Insert the string "1 user" or " users" where is the number of current users logged in.
\v : Insert the version of the OS, eg. the build-date etc.