Use ssh-keygen to Create SSH Key Pairs and More

Learn how to use ssh-keygen to create new key pairs, copy host keys, use a single login key pair for multiple hosts, retrieve key fingerprints and more in this tutorial.

Logging into remote systems with SSH implementations is secure by default -- but those connections are secured only in that they use the TLS protocol to encrypt network protocol exchanges. SSH can be made even more secure by using it to authenticate communicating hosts through the exchange of public keys -- keys that are created using the ssh-keygen command.

This tutorial shows how to use the ssh-keygen command to create a new public key and how to use that key to do the following:

• upload the public key to a remote server to enable automated and authenticated logins;
• use the same public key on multiple remote servers; and
• use multiple public keys for different functions on the same server.