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Using the issue file
The issue file, also found in the /etc directory, shows a message on the local terminal, just above the login prompt. A default issue file would just contain macro code that would show information about the machine. Look at the following example:
Ubuntu 16.04.3 LTS \n \l
Or, on a CentOS machine:
\S
Kernel \r on an \m
On an Ubuntu machine, the banner would look something like this:
![](https://epubservercos.yuewen.com/EB7950/19470399001594806/epubprivate/OEBPS/Images/Chapter_23.jpg?sign=1738972917-Z6dIH3F3wMh2gbfESajYWzBEjrOwWKCn-0-c4b2117f229df572324d1a222b7eaa95)
On a CentOS machine, it would look something like this:
![](https://epubservercos.yuewen.com/EB7950/19470399001594806/epubprivate/OEBPS/Images/Chapter_60.jpg?sign=1738972917-UFKrIbyEGl7sj6D8SCx6mqgMU1knHGJl-0-e9a2a5af09bcecd29250a6cccfa32703)
You could put a security message in the issue file, and it would show up after a reboot:
![](https://epubservercos.yuewen.com/EB7950/19470399001594806/epubprivate/OEBPS/Images/Chapter_48.jpg?sign=1738972917-gIyWYMVAaTrcF1Z0tItXmcJBgQe2BEHi-0-919b8b1dee48bbad40e197c4f9845965)
In reality, is there really any point in placing a security message in the issue file? If your servers are properly locked away in a server room with controlled access, then probably not.