The Secure Shell (SSH) in Linux is used to log into the machine in an encrypted and safe manner. This helps in providing a secure channel to streamline all requests to the Ubuntu server. SSH uses cryptographic keys to log into the server.
On Windows, the most common tool to perform a secure shell to a Linux server is putty. In this chapter, we will learn how to use putty to Secure Shell into a server.
Step 1 − Download putty from the http://www.putty.org/ site.
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Step 2 − Before connecting to use putty, we need to know the IP address of our Ubuntu box. To do this, type ifconfig in the command shell of the Ubuntu server.
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From the above screenshot, we know that the IP address of the server is 192.168.0.20
Step 3 − Next step is installing SSH on the server. In order to SSH to a server, you need to make sure it is installed. Run the following command in the Ubuntu server command prompt session.
sudo apt-get install openssh-server
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Step 4 − Launch PuTTY. Enter the IP address of the Ubuntu server and click the Open button.
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Step 5 − The next screen requests to accept the encrypted key sent from the server.
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Step 6 − Finally, enter the username and password to log into the server. We have successfully established a secure shell to the server.
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