How to enable key based authentication

Enable key based authentication

1. Generating Keys

Key generator is available with Putty to generate private and public keys. You can download PuttyGen from here, download Putty.Gen.

1.1 Open PuttyGen and click on Generate button to create your keys.

Putty keys

1.2 Generate randomness to create keys.

randomness to create keys

The key passphrase option enables additional security.

1.3 Save private key on the local machine.

private key

2. Adding the public key to server

After generating keys we need to add the public key into the server’s authorized_keys file. This file is in the location “/root/.ssh/authorized_keys“;

2.1 Adding key

# vi /root/.ssh/authorized_keys

If it’s not there, create it.
For security reasons, change the file and folder permissions as follows:

[root@hostripples ~]# chmod 600 /root/.ssh/authorized_keys [root@hostripples ~]# chmod 700 /root/.ssh/

vi /etc/ssh/sshd_config
AuthorizedKeysFile      .ssh/authorized_keys

If you need to enable only key based authentication in your server, disable password authentication.

PasswordAuthentication no

2.3 Restart SSHD

[root@vps ~]# /etc/init.d/sshd restart
Stopping sshd:                                             [  OK  ]
Starting sshd:                                             [  OK  ]

3, Final step : Connecting to server

Now we have to check whether the keys are working. Please follow the steps to connect server using key.

3.1 Create a “Saved Session”

Here you need to create a new saved session for your key based connection. Mention server IP address, SSH port and session name.

3.2 Add user name

Under “Connections >> Data” add user name to connect to server.

3.3 Add private key

Under “Connections >> SSH >> Auth” you can select the private key that we saved in our machine.

That’s it! Then come to session and save.

Try to connect now 



Vishwajit Kale

Vishwajit Kale blazed onto the digital marketing scene back in 2015 and is the digital marketing strategist of Hostripples, a company that aims to provide affordable web hosting solutions. Vishwajit is experienced in digital and content marketing along with SEO. He's fond of writing technology blogs, traveling and reading.