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# You should see a number of packages installed including <b>openssh-clients</b> and <b>openssh-server</b>
# <b><code><span style="color:#3366CC;font-size:1.2em;">openssh-server</span></code></b> installs a service called '''sshd'''. Confirm that this service is running by issuing the command:<br /><b><code><span style="color:#3366CC;font-size:1.2em;">service sshd status</span></code></b>
# Also, you should confirm that the sshd service is enabled (to start automatically upon boot-up). To do this issuing the following command:<br><b><code><span style="color:#3366CC;font-size:1.2em;">systemctl list-unit-files | grep sshd</span></code></b><br><br>'''NOTE:''' the ''netstat'' is a very useful command for anything to do with networking. Read the man pages and make sure you understand the netstat command's output.<br><br>
# Now that you know the service is running, investigate what '''port number''' and '''protocol''' sshd uses by issuing the command:<br /><b><code><span style="color:#3366CC;font-size:1.2em;">netstat -atunp</span></code></b>
# What protocol and port is the sshd process using? What is the state of the port? Why would you think that UDP ports don't have a state?
# Reissue the <b><code><span style="color:#3366CC;font-size:1.2em;">netstat</span></code></b> command without the '''-n''' option. What is the difference?
# How is the file '''/etc/services''' related to the difference?
# '''netstat''' is a very useful command for anything to do with networking. Read the man pages and make sure you understand the netstat command's output.
# Make sure the '''sshd''' service is running on '''all 3 of your VM's'''