How to Generate an SSH Key
The first step to setting up an SSH key is to generate a pair. An SSH-key pair contains a public and private key. Using the public and private pair, you can authenticate a user to a remote host.
In Linux, use the following command to generate an SSH key pair:
The above command will require you to input information to set up and create the keys. If you are on unsecured networks or critical systems, be sure to encrypt your keys with a passphrase.
Enter file in which to save the key (/home/ubuntu/.ssh/id_rsa):
Created directory '/home/ubuntu/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/ubuntu/.ssh/id_rsa
Your public key has been saved in /home/ubuntu/.ssh/id_rsa.pub
The key fingerprint is:
SHA256:hVkOnzk7nLWx3j4vqLv/B83tYN7w3juLAbFw610xh7Q ubuntu@CSALEM
The key's randomart image is:
+---[RSA 3072]----+
| . . . |
| B o . o |
| o.Boo Eo.|
| oo=++ +|
| S =+o +.|
| .oo.* +|
| ..*.B |
| ..*.*|
| +=.ooOB|
+----[SHA256]-----+
NOTE: You must have the OpenSSH package installed on your system to use the ssh-keygen command.
How to View an SSH Key
The first method that you can use to view your SSH key is by using a simple cat command. This command will print the file’s contents, which you can copy and paste to the remote host. By default, SSH keys are stored in the /home/$USER/.ssh
To view the contents:
cat id_rsa.pub
The above command will print the contents of your SSH public key. The following is an example key:
Another method that you can use to view the contents of your SSH key is by using the Open-SSH authentication tool with the command shown below:
This command will prompt you for an authentication password for the passphrase if one is assigned, as follows:
Identity added: /home/ubuntu/.ssh/id_rsa (ubuntu@CSALEM)
ssh-rsa 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 ubuntu@UBUNTU
Conclusion
This article showed you how to generate an SSH key, as well as two methods that you can use to view the content of an SSH key. For the most part, you will only need to view the content within public keys, and not private keys. Always make sure to protect your SSH keys at all times. Secure your Shell!
