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OPS235 Lab 7 - CentOS7

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# Use your '''centos2''' VM to complete this section.

# ~~Establish~~ Open a terminal and run the '''netstat''' command (pipe to "grep sshd") to check the state of the connection. What is the state (i.e. LISTENING or ESTABLISHED)?# Open another terminal and establish an ssh connection to your '''centos3 ''' VM using the command: <code>ssh ops235@centos3</code> (Where 'ops235' is the account on centos3 and 'centos3' is the hostname of the centos3 VM.)

# You should receive a message similar to the following:

#::The authenticity of host 'centos3 (192.168.235.13)' can't be established.

# Issue the following command to confirm that you connected to your centos3 VM: <code>hostname</code>

[[Image:spoof.png|thumb|right|485px|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)]]

<ol><li value="6">~~Logout~~ Switch back to the original terminal and re-run the netstat pipeline command again. Any change to the connection status?</li><li>Return to the second terminal, and logout of your ssh connection by typing <code>exit</code>.<li>Run the netstat command in ~~another~~ the original terminal and 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 centos3 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>

Msaul

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