====== Configure Key-based Authentication ======

**General Information**

SSH key based authentication (password-less).

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====== Lab Setup ======

The following virtual machines will be used:
  * server1.example.com (192.168.1.150) -> The SSH client
  * server2.example.com (192.168.1.151) -> The SSH server

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====== SSH Key Creation and Distribution ======

Key based authentication involves a private and public key.\\
The private key stays on the source system, the public key is distributed to all remote systems.

Generate the private/public key pair.
<code bash>
ssh-keygen
</code>
  * RSA is the default key type
  * Prompted for file to save private key (~/.ssh/id_rsa)
  * Prompted for file to save public key (~/.ssh/id_rsa.pub)

\\
Copy the public key to a remote system
<code bash>
ssh-copy-id myserver
</code>
  * Prompted for password login
  * Next normal ssh login will be password-less

\\
__**Key Pair with Passphrase**__

If you created the key pair with a passphrase, it is useful to cache the passphrase for a bash session to avoid re-entering it for each ssh connect.

\\
Start the ssh-agent for the current shell
<code bash>
ssh-agent bash
</code>

\\
Add the passphrase
<code bash>
ssh-add
</code>
  * Prompted for the ssh key passphrase

\\
Connect as normal with ssh, you should not be prompted for a password if the public key has already been copied to the remote server.

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