When you first install Ubuntu Desktop you will not be able to SSH onto the machine from another host because you need to install the OpenSSH server. This short post will show you how.
Open up Terminal and issue the following command.
sudo apt-get update
sudo apt-get install openssh-server -y
Enter your password when prompted and wait for the server to be installed.
Connect from another Host
Now assuming your username is ubuntu and IP address is 192.168.1.211, run the following command from another host on the network.
If all goes to plan, you should now be asked for your password and you will be logged into the system.