Changes

{{Admon/note |POSSIBLE DNS SPOOFING DETECTED | If you receive a message like the one displayed above, you should investigate why it is happening as it could indicate a serious security issue, or it could just mean that something on the host has changed, i.e. the OS was reinstalled.}}

<li>Establish an ssh connection using your learn account from fedora3 to fedora2.</li></ol>

{{Admon/note | | When you have both ssh connections established between fedora2 and fedora3 check your network connections using the netstat command. You should now see at least 2 TCP connections with a state of ESTABLISHED. One connection represents the connection from fedora2 to fedora3 and the other represents the connection from fedora3 to fedora2. You should also see that you still have ssh listening to TCP port 22. Notice that the client side of each connection uses a random port number in the upper ranges. This common behaviour for client side applications.}}

<li>Check the state of the connection after logging out. Wait a few minutes and then check again. Record your observations.</li>

<li>Make certain to exit all connections, and that your shell is located in your <u>Fedora2</u> server. You can verify this by entering the command: <code>hostname</code>

<li>Use the Internet to search for "TCP 3 way handshake" to see how TCP connections are established and closed.</li></ol>

{{Admon/tip | Tip: | In this part of the lab you established an ssh connection to another host using a password to establish your identity. But passwords are not the only or even the best way of authenticating your identity. We can also use Public/Private key encryption.}}

=== Investigation 3: How do you establish an ssh connection using Public Key Authentication. ===